Challenging the Levels: The Catholic Church as a Multi-Level Actor in the Transition to a Climate-Compatible Society

: Climate compatibility is a cornerstone in the ecological transformation of modern society. In order to achieve sustainable development in all areas of society, numerous social actors must participate. This article examines the potential for the Catholic Church in German-speaking countries to contribute to such change. To this end, in contrast to most current studies, the Church is conceptu-alized as a multi-level actor instead of focusing only on the top of the hierarchy. Case studies are used to explore how various Church actors in different ﬁelds of social action evoke ecological awareness among members and non-members alike or participate in changing social structures.


Introduction: Religion as an Agent of Change in Shaping a Climate-Compatible Society
"We are the first generation that can put an end to poverty and we are the last generation that can put an end to climate change, so we [must] address climate change. These opportunities coincide with a time of unease for the human family", declared Ban Ki-moon [1]. In September of the same year, 2015, the United Nations Summit on Sustainable Development adopted the resolution Transforming our World: The 2030 Agenda for Sustainable Development. This agenda encompasses 17 "Sustainable Development Goals" (SDGs), defined for 169 associated targets and tracked by 232 indicators [2]. They cover a wide range of social, ecological and economic challenges that must be addressed together by 2030 to allow for sustainable development for the whole world community [3]. Together, they outline a roadmap for all nations toward a fairer and ecologically more balanced world. In order to achieve the sustainable development goals set out in the Sustainable Development Agenda, comprehensive transformation efforts are needed at the global, national and local level. All societies and communities must participate. Technical solutions or increased efficiency alone will not achieve the goals. Cultural transformation efforts are equally important to enable a more sustainable future. One important cultural area is religion [4][5][6][7][8]. This article examines how a specific religious community, namely the Catholic Church in German-speaking countries, contributes to the shaping of a sustainable and, in particular, climate-compatible society.
In order to understand the SDGs in a more general context, it is essential to examine their emergence from the Millennium Development Goals (MDGs). A comparison underlines three major differences: 1.
The SDGs consider-much more than the MDGs-the environmental aspects of development, whereas the year-2000 aims concentrated primarily on the socio-economic aspects: on the fight against poverty through the reduction of extreme need and hunger, the prevention of deadly diseases and the expansion of primary education to all children. MDG 7 might be seen as an exception, since it calls for the ensuring of environmental sustainability; it stays, however, quite general in its approach. change in the fourth section, the conclusion links the findings back to the ethical principle of subsidiarity, which highlights the aspect of supportive cooperation in hierarchical relations. In this article, we argue that religions are an important societal force that can implement climate-compatible lifestyles and foster sustainable development on a local, regional and global level. More than 80% of the world's population is affiliated with a religion [32], which makes religions influential in shaping society. They can have a conservative and preserving effect, or they can initiate, sustain or guide change [33,34]. The latter aspect will be explored in this article. Since religions may differ in their worldviews, rites and social organization, the following observations focus on the Roman Catholic Church, concentrating primarily on the geographical area of the German-speaking countries. The rather favorable legal situation allowed the Catholic Church in these countries to develop a good organizational agency, which is why an exploration of its activities in climate protection is worthwhile. Due to the historical development, cooperation with other Christian denominations or with civil society groups is typical; many activities aim therefore at an unspecified broad public.

Materials and Methods: The Different Levels in the Catholic
In order to illustrate the different ways in which the Catholic Church contributes to societal change, the following chapter analyzes several ecclesiastical groups of actors, forms of action and fields of activity by way of example and based on the resource materials published by these actors without focusing on the effectiveness of these activities. The guiding thesis here is that these activities should always be seen as a niche activity, as will be explained in more detail in Section 2.2. In view of the fact that the variety of the Catholic Church's engagement in the different fields of climate protection has not been evaluated in detail so far, diverse examples from a broad spectrum were deliberately selected to provide an overview.
To fully understand the Catholic Church, different perspectives must be adopted at the same time, an approach that has thus far rarely been implemented in transformation studies. The Catholic Church is a specific denomination within Christianity. It is a global community which is organized geographically in dioceses. These are connected to each other in national and continental bishops' conferences. Important parts of the Church's pastoral work and administration are fulfilled by priests; nevertheless, the Church understands itself as a community of all the faithful: The decisive criterion is baptism [35] (n. 30). Hence, any analysis of the Church cannot limit itself to the actions of priests and the formal ecclesial organization, much less to papal statements. On the contrary, it must consider the multitude of ecclesiastic communities. In addition to parishes, these comprise monasteries and orders, a large number of religious associations (which differ from country to country) and various institutions which are often legally independent but nevertheless act as a part of the Church, such as nursery schools, hospitals, retirement homes or sheltered workshops, which in Germany are often run by the Caritasverband. In the same way, research must also take account of the actions of individuals whose identities combine, often indistinguishably, the many roles of the modern person, among them the religious role [36][37][38].
Considering the Catholic Church as an agent of change is not just a perspective from outside but touches on the very self-understanding of this community. Although the Church is not a political group in the way that a party, trade union, social movement, NGO or pressure group is, the commitment to a better world is part of its mission to announce the gospel of the loving God in deeds and words. In order to do so, it must read the "signs of the times" [39] (no. 4.11), [40]. The excessive overuse of nature in a multitude of practices that cumulatively result in climate change, together with a growing ecological awareness, is certainly a characteristic trait of the 21st century, a typical "sign of the times". This is why different Christian churches have developed a multifaceted environmental consciousness during recent decades. This happened in many cases through ecumenical cooperation. Additionally, the impact of a fruitful and respectful dialogue with various partners, be that research institutes or NGOs, is also paying off [41][42][43][44]. Therefore, in the following paragraphs only the most prominent milestones in official teaching and proclamations will be mentioned in order to briefly illustrate the most important aspects of the Catholic Church on the regime level. Regardless of their differences in emphasis, they embed their thoughts in a framework of theology of creation.
Over the decades, ecological awareness and practical efforts to protect the environment have become more and more visible. The recent publication of the encyclical Laudato si' [45] can be seen as the culmination of Christian environmental commitment to date. However, it is certainly not the only evidence of the emergence of a Christian interest in ecological concerns.
The first encyclical letter that broached environmental issues, albeit obliquely, was Pope Paul VI's encyclical on development, Populorum Progressio (1969) [46]. It was written in light of the then widespread belief that the challenges humanity faced could be resolved by human efforts, which now may sound rather optimistic. Pope John Paul II adopted his own approach, called "human ecology", which concentrated on the relationship between humans and their natural, social and built environments and related humans' inner nature to their outer environment.
The focus of both these comments was social justice for the poor, who were also impoverished by the deterioration of their natural environment. Hence, these approaches remained anthropocentric. Pope Francis broadened this perspective, yet without strictly adopting a physio-or ecocentric worldview.
On the one hand, national and regional efforts had paved the way for, and sustained, this development. The German Bishops' Conference, for example, was one of the forerunners. It published its first pastoral letter on environmental issues, Zukunft der Schöpfung-Zukunft der Menschheit (Future of creation-future of humanity) more than a generation earlier than Laudato si' [47]. Since then, it has issued numerous other statements, expert texts and working aids on sustainability in general and climate protection in particular [48,49].
On the other hand, the increasing awareness of environmental issues was embedded in ecumenical cooperation. At the 1974 World Council of Churches (WCC) conference in Bucharest, sustainability became a keyword and a guiding principle for a future society in Christian thinking, which was expressed in a communiqué under the title Sustainable and Just Society (1974) [50]. The authors were committed to the idea that ecological limits had to be respected in order to create a society that was also economically sustainable over the long term. The Nairobi conference (1975) adopted this paper as an important complement to the ecumenical and social thinking of the WCC.
These thoughts, which were developed on a world-wide level in a Christian ecumenical context, were then applied to the European context. Unlike the global WCC activities, the Catholic Church became a partner on the European level. The 1980s and 1990s in particular were shaped by reflections on the socio-ecological context. The Church led, inter alia, in the Conciliar Process for Justice, Peace and Integrity of Creation (JPIC) with three significant ecumenical meetings held in Basel (1989), Graz (1997) and Sibiu (2007) [3,42,[51][52][53].
Finally, in recent years there have also been new impulses from the Orthodox Church, especially from Bartholomew, the patriarch of Constantinople and therefore a major point of reference in the Orthodox world. "Aware of the dramatic social and cultural impacts that people face as a result of climate change", he made an urgent appeal to the public to step up for the protection of the environment [54,55].
Irrespective of all efforts by the churches to develop impulses from the Christian faith tradition to move society, as well as individual churches themselves, in a more sustainable direction, there are also tendencies which contrast faith and social practice more strongly. While the communiqué Sustainable and Just Society (1974) emphasized the unity of economic and religious concepts, the follow-up study Just, Participatory and Sustainable Society (1976) viewed them as opposed in a fundamental way [50,56]. In interpreting "sustainability" in an exclusively God-focused way, this term was used as a synonym for God's care for the world, and economic terms got lost in favor of an exclusively religious vocabulary. This was illustrated by the later renaming of the field as "integrity of creation", an expression which was also adopted from the Conciliar Process for Justice, Peace and Integrity of Creation [57] (pp. 180-183), [52,[58][59][60].
Yet, several new movements and activities are trying to combine these perspectives and to break up dichotomies like religious/inner-worldly. Instead, they understand the Christian faith as providing an impetus to change everyday life and society according to the Gospel.
Changing everyday life and society according to the Gospel-hence, developing good lifestyles and high-quality social relations and institutions-requires the cooperation of various actors, institutions, ideas and trends on multiple levels. In the field of social ethics, these complex relations and interdependent interactions are often considered from the perspective of subsidiarity [18,[61][62][63][64][65][66][67][68].
Subsidiarity as a social principle is a guideline for structuring society and for the conduct of major societal institutions. It was established in the Catholic Church with an "official" formulation in the encyclical Quadragesimo Anno (Pius XI, 1931): "Just as it is gravely wrong to take from individuals what they can accomplish by their own initiative and industry and give it to the community, so also it is an injustice and at the same time a grave evil and disturbance of right order to assign to a greater and higher association what lesser and subordinate organizations can do. For every social activity ought of its very nature to furnish help to the members of the body social, and never destroy and absorb them." [69] (no. 79) Since then, this principle has undergone a process of readjusting, in recent years under the aspect of civil society [40] (pp. 196-214), [70,71]. The central idea is threefold. First, it means that the autonomy and the competence to solve a problem should be left to, or conferred onto, that actor who is closest to the problem. Second, since many problems or tasks are demanding, extensive and time-consuming, subsidiarity fosters the development of cooperation. Finally, the multitude of actors who form a unity in one way or another are asked to coordinate their purposes in a just way. In a nutshell, subsidiarity means that more central organizations must assist, rather than paternalistically taking over competences from, more local organizations. All parties involved must be careful not to do too much or too little. In regard to societal change, this means that it is not always the individual actor's task to contribute new ideas, but each level must contribute in its unique way, as the examples in Chapter 4 show.

The Multi-Level Approach to Explore Transformation
In order to analyze the Catholic Church's contribution to societal transformation, we apply a multi-level approach and show that this analytical method can be used to examine the places and the ways where and whereby the Catholic Church is dealing with the challenges of climate change. To this end, it describes the Church as a special actor: as a community of interrelated agents of change on different levels.
The multi-level approach which is used here builds upon the model of Geels et al. [72][73][74][75]. Societal transformation processes take place on three different but interconnected levels. The central level is the "regime level" or the "sociotechnical order". It encompasses (a) different sociocultural practices; (b) framing rules and institutions, such as juridical and technical norms, cultural habits and role models, or economic relationships; and (c) the material base, i.e., infrastructure, machines and so on. A sociotechnical order is always embedded in a larger "sociotechnical landscape" that is shaped by fundamental political, economic and cultural patterns like democracy, legal constitutions, the free market economy or individualism, as well as long-lasting trends. Sociotechnical change usually begins in "niches", or protected spaces in which technical, cultural or economic innovations can arise.
Two factors are necessary for lasting change: external pressure and pioneers who try out new techniques, machines or practices. In current times, such external pressure is already noticeable, as the "planetary boundaries" are exceeded in many areas [76,77]. This natural pressure is transformed into societal pressure, expressed not only by environmentalist groups, but also by directly affected economic actors like farmers, fishers or large food companies. This in turn engenders a change in mentality, which can be the basis for further transformation programs. A great transformation cannot be planned from the top down in a sociotechnical manner. Instead, it must be test-driven by pioneers who simply do "business unusual". With changes in the sociocultural order, such niche innovations can find new favorable conditions and spread.
This model implies some important methodological considerations. First, there is no monocausality. Niche actors, or "pioneers", can invent some fundamentally new way of acting or a novel device, yet the innovation needs several explicit and implicit supporters if it is to be implemented on the regime level. The same is true for top-down approaches like legislation. Second, innovations may be, sometimes fundamentally, altered on their way from a niche to the regime level. Third, motivation and effect must be distinguished. Some innovations are just a byproduct of another action, and some forms of support are just a means to another end. Hence, what at first glance looks like a neat three-level scheme is a dynamic and complex network with many local or instable sublevels and with comprehensive patterns, as the following analyses will show.
The Catholic Church as an agent of societal change is, as we will show, a multilayer actor. Its structural diversity needs to be given much greater consideration when referring to it as an actor in the field of "greening". Different levels produce different impulses in different processes. This multitude has so far only rarely been considered in transformation research. Therefore, this study takes as an example the Catholic Church in German-speaking countries to analyze the variety of possible actors and actions within a single religious community.
In order to give a better overview of the Catholic Church as an agent of change, it may be helpful to distinguish the three above-mentioned levels within the Church: The meso-level, i.e., the patchwork of regimes, might be qualified as the analytical starting point [78]: Here, these regimes are understood as ecclesiastical structures and well-rehearsed behavior patterns. They encompass the territorial division of dioceses into parishes, as well as the network of numerous federations with many members, which often offer regular group meetings. Pastoral activities are divided into diaconia (solidary support), liturgia (services), martyria (annunciation of the Gospel) and koininia (community building), which, in addition to more familiar forms of pastoral care, also include educational, media or district work. A part of the regimes that is still culturally formative is the church year with its feasts, seasons and imagery, even if attendance at Sunday services is declining. Significant architectural centers are buildings such as churches, parish homes or community buildings, e.g., for kindergartens and schools. An important basis of the regimes is the economically and legally relevant structure of parish funds, which often include real estate and agricultural land. They enable ecclesial work on a high level, e.g., through the possibility of paying qualified personnel adequately. Another aspect of regimes are the national Bishops' Conferences, which maintain various expert commissions, especially in Germany, that regularly comment on current social issues.
All these material and ideal structures create stability in regard to the expectations and behavior of the members and the social environment. On the other hand, this strict form of organization might also lead to institutions becoming fossilized and make changes more difficult.
The layer above the regime level is that of landscapes, which subsume more general trends, such as pilgrimage, spirituality and ecological conscience, as well as the decline in church-bound religiosity. These trends are not restricted to the church but can be observed on an overall societal level. Nevertheless, they have an impact on the church sphere, just as church regimes may influence other spheres in the manner of reinforcing, slowing down or realigning.
Impulses for change often emanate from the level of niches, i.e., from spaces or groupings that can try out new things and develop these ways of seeing and acting relatively undisturbed by external influences. In some cases, such changes are expanded to the regime level through various selection and reinforcement processes. Having reached this level, they might become permanently established so that they change the regime. In this way, little changes can influence the higher-level landscape.
One example is monasticism, which is also found in religions other than Christianity. Individual monastic communities, i.e., both monasteries and religious orders, represent a social association that lives within the universal church according to its own rules and in self-directed distancing from the social environment. Therefore, new ways of seeing or behaving can easily develop in their ranks and possibly spread worldwide within the structure of an order without leaving the niche level. The new characteristic may then be present worldwide, but from a social point of view, it is only anchored in a very limited group. One such new development was the institutionalization of charitable care for the poor and sick. As early as the 4th century, monasteries established xenodochia and hospices and thus assumed an important social function in cities [79]. In this way, they changed the ecclesiastical structures and practices of diaconia as well as the social order of care at the regime level, thus contributing to their institutionalization and professionalization in the long term, i.e., at the landscape level.

Results: The Catholic Church-A Change Agent: Potentials on Different Levels
The following section presents seven different examples that show the commitment of specific actors within the Catholic Church to achieving a climate-compatible society. Some activities relate directly to climate action as a single issue, while others are embedded in the broader perspective of ecological awareness and sustainability.
These studies explore how the Catholic Church, as a multi-level change agent, drives social change that is considered as necessary to reach climate neutrality. The subjects of the study should be deliberately diverse: social fields of action, working groups and networks, papal circulars, programs or spiritually shaped times. In other terms, these areas of engagement might also be classified as ideological, organizational and practical. The examples are presented in a loosely chronological order.

Environmental Commissioners and Their Networks
Ecclesial attention to environmental degradation differs-as do most other manifestations of Church engagement-from country to country. The emergence of an environmental engagement is largely a result of the existence of religious One World Groups, which have interacted with a general trend of global solidarity since the 1970s.
In Austria, the Diocese of Linz founded the first working group for environmental issues in 1991. In 1992, the Working Group Responsibility for Creation (ARGE Schöpfungsverantwortung) was founded, and two years later, the Austrian Bishops' Conference established its own department for ecology. Finally, in 2000, the diocesans' environmental commissioners joined in forming a conference that sought ecumenical exchange with partner organizations.
Protestant and Catholic dioceses in Germany work in a similar way. The diocesans' environmental commissioners have an official position in the diocese's administration, act as advisors for the diocese's administration as well as at the community level, provide impetus, and network the environmental work of the church with that of non-church groups. Despite their social significance and their widely recognized theological relevance, these positions are usually quite limited in their scope and in their ecological impact. In order to anchor these efforts more firmly in local contexts, voluntary environmental commissioners have recently also been sought at the community level. The field of activity is large and often relates to local issues, yet climate action is always a central task.
In contrary to the above-mentioned countries, the situation in Switzerland is different: Instead of environment managers employed by the church, care for creation is outsourced to the interdenominational (Reformed and Roman Catholic) association "oeku Kirche und Umwelt", which struggles therefore with a much less established standing and less financial support but has potentially more liberty to approach new issues [80]. It regularly publishes brochures on environment-related questions. It also supports parishes and congregations on their path towards gaining an ecological certification called "the green rooster" [81].
The foundation of the European Christian Environmental Network (ECEN) resulted from the second European Ecological Assembly in Graz in 1997 [82]. It coordinates the cooperation of ecclesial work in the ecological field on the European level.
The example of ECEN confirms what has been said above: In the ecclesial context, the differentiation of the various levels remains difficult. Even if ECEN is a niche, this is not to be understood in spatial or geographical terms but results from its thematical (environment) as well as social (officially assigned actors) restriction. Furthermore, it is a good example of cooperation between several actors at different hierarchical and coordination levels in accordance with the principle of subsidiarity. ECEN as a spatially superordinate body has the task of coordination but should not and cannot replace or steer the work at the grassroots.

Car Fasting: A Programme for Ecological Contemplation
Catholic dioceses and Protestant regional churches in Austria, Germany and Luxembourg have been calling for car fasting for over 20 years-yet, in Luxembourg, the program was stopped in 2019, and in Germany, after the COVID-19 pandemic, the program will not be restarted again in 2021 [83,84]. It consists of reducing car use and individual motorized traffic during Lent, the religious period of preparation before Easter. The practice of car fasting allows for this traditional time of (spiritual) recollection and temporary changes in habits to be re-interpreted in an ecological way. It receives support from several nature conservation associations, such as Bund für Umwelt und Naturschutz Deutschland e.V. (BUND; Friends of the Earth Germany) or Naturschutzbund Deutschland e.V. (NABU), as well as from traffic clubs such as Verkehrsclub Österreich (VCÖ), local and regional traffic associations, municipal networks such as Climate Alliance Austria and political actors.
The initiative is open to, and directed at, society in general in addition to church members; spiritual practices (e.g., prayers), educational measures and political appeals come as a plus. Nevertheless, the Christian responsibility for creation and society provides the background and motivation for the project. It links the characteristics of mobility with climate change and reflects citizens' global and intergenerational responsibility. Strengthening biking as a means of transport and the use of public transport in general is one aim, but not the only one.
The concept of car fasting developed undisturbed as a thematically, temporally, spatially and socially limited measure that originated with the environmental commissioners. Inspiration came from a combination of general environmental awareness and specifically religious responsibility for creation. Therefore, an alliance with other actors was established, which received further support from critics of motorized individual transport over time. Subsequently, the general climate protection movement proceeded to include car fasting in a more general way and created a more solid anchorage for the practice at the diocesan and national church level. The cross-national connections were a logical next step and contributed to an even bigger strengthening of ecological awareness in society.
In the meantime, this approach of ecologically conscious and socially committed fasting has become more widespread, and church authorities, in cooperation with environmental associations, are calling for fasting for the climate, or even plastic fasting.

Season of Creation
A good example to illustrate how much spiritual, liturgical, everyday practical and socio-political activities can go together in religion is the Season of Creation. In 1989, the Orthodox Patriarch of Constantinople, Dimitrios I, suggested that each first of September should be celebrated as a "day of preservation of the natural environment". The European Christian Environmental Network (ECEN) took up this impulse at its second meeting in 1999 [85]. Finally, in 2007, the Third European Ecumenical Assembly of Churches, held in Sibiu, Romania, in the framework of the Conciliar Process for Justice, Peace and Integrity of Creation, formulated the proposal of a Creation Time. The period between 1 September and 4 October-the day of commemoration of Francis of Assisi, declared the patron saint of ecology and those who promote ecology by Pope John Paul II in 1979, was to be anchored in the church year as a season in its own right. The protection of creation and the promotion of a sustainable lifestyle in worship, prayer and active practice are core issues during this time [86].
The German churches took up this proposal. During the 2nd Ecumenical Church Day in Munich in 2010, the Working Group Christian Churches (Arbeitsgemeinschaft Christlicher Kirchen) designated the first Friday in September as the "Ecumenical Day of Creation". The end point of Creation Time is the Harvest Festival, which is celebrated in Germany on the first Sunday in October. Since 1993, the above-mentioned Swiss association oeku has prepared annual proposals that are relatively well-accepted in Catholic and Reformed parishes in Switzerland [87]. Finally, in 2015, Pope Francis proclaimed 1 September the "World Day of Prayer for Creation". Even if these ideas are far from being applied in all parishes, this example shows that there is a high potential for ecological awareness within the Church(es).

"Buying for the Future": Church Procurement
The Catholic and the Protestant (in Switzerland, Reformed) Churches are major consumers and increasingly want to meet this demand in sustainable ways. The procurement volume of the Catholic and Protestant churches in Germany totals an amount in the high double-digit billion range each year [88]. In addition to parishes and church administrations, the large church institutions such as hospitals, retirement homes or educational institutions (often run by Caritas) contribute to the high amount of consumption.
The Catholic Caritasverband and its Protestant equivalent Diakonieverband are welfare organizations that operate within state social legislation, yet also as parts of their respective Churches. Both of them resulted from the social differentiation process during the time of modernization. Numerous charitable institutions adopted a modern organizational structure. They operate in accordance with professional (medical, nursing, educational, business management, etc.) standards without ceasing to be an essential part of the church. This situation must be seen in the particular German and Austrian context. The law governing state-church relations ensures the (financial) viability of the recognized churches through church tax. At the same time, in accordance with the principle of subsidiarity, the charitable organizations have priority over state activity and are financed by the state.
In order to ensure that procurement is climate-compatible, ecologically sustainable and socially just over the long term and also to provide planning security for suppliers, several regional Caritas and Diakonie associations and church communities in Germany joined forces in 2008 to form the initiative "Buying for the Future" ("Zukunft einkaufen") [89]. This enabled them to pool their market power and to sustain their relationship with regional producers in the region and in other parts of the world. At the same time, internal learning and development processes were initiated in this way. The pilot project has since developed into a nationwide network that also radiates into neighboring countries. The initiative is motivated by the central Christian values of the preservation of creation and justice, as well as by the concern for the credibility of the Church as an actor in civil society.

Laudato si': An Encyclical Letter Concerning Our Common Home
Pope Francis's encyclical letter Laudato si' (2015) was the first papal encyclical to address global ecological degradation, and climate change in particular, as violence against non-human creatures and a social sin against the poor and future generations. It has received enormous attention within and without the Catholic Church and the religious sphere, in politics as well as academia, including the field of research on the "greening of religion" [45,[90][91][92][93][94][95][96]. Some even went so far as to detect a "Francis effect", attesting that the Catholic Church and Christianity in general were experiencing a long-needed and waited-for turn to ecology and sustainability [97,98]. This, however, ignores a lot of the above-mentioned activities: in particular, the manifold practical movements, as well as the more theoretical debates on ecological issues that have been taking place for decades.
The encyclical is here assigned to the level of the niche and not to the level of the regime or the landscape, in so far as it addresses a new theme and tries out new patterns of thought within the papal writings and the magisterium of the Church. It is a pioneer in this respect, even though it has not brought the theme of ecology into Church discourse anew.
An encyclical alone does not achieve anything. Rather, it must resonate with the faithful, find sufficient support in the episcopate and be integrated into church structures and programs. This was the case with Laudato si', as the following examples of church environmental education and Christian climate-protection activities show.
A particular strength of the papal circular as it is taken up and further developedwith approval both within and outside the Church-is the fact that it opens up new horizons instead of prescribing positions [99,100]. It provides a variety of impulses for developing one's own viewpoint and behavior. In doing so, it links the individual and the collective dimension, the level of virtue and the level of structures, in a differentiated way. This increases the ability to connect with various actors and discourses within and outside the Church according to the principle of subsidiarity.

Environmental Courses in Education
An important field of activities that has received little attention in environmental studies so far is the Catholic Church's engagement in (adult) education. It covers churchsupported kindergartens and schools, religious education at state schools (in Germany, Austria and various parts of Switzerland), informal education in youth groups as well as the broad field of extra-curricular adult education, a field in which various German associations are very active (e.g., Katholische Erwachsenenbildung e.V., Kolpingwerk) [101][102][103][104].
For some years now, the number of courses with an ecological focus has been increasing significantly, since 2015 strongly supported by the encyclical letter Laudato si' [105][106][107]. Some, such as lectures and seminars, are cognitive in nature; others, like spiritual hikes and mountain tours, appeal to experience; and yet others like "climate cooking courses" focus on practical skills for a sustainable lifestyle. In the programs of the educational institutes, they are assigned to the subject areas of "meaning and orientation", "society", respectively, "environment-peace-society", "responsibility for creation" or "spirituality".
The program "Living a life suitable for our grandchildren" ("Enkeltauglich leben"), in which people discuss and try out lifestyle changes with future generations in mind, was particularly successful [108]. The name introduces the concept of sustainability in an everyday and non-moralizing way by referring to the aspect of intergenerational relations. The course picks up on impulses from the post-growth movement and the common welfare economy and makes the basic idea of sustainability tangible in a playful way.
Similar to the car-fasting project, here, too, it can be seen how certain Church actors participated in a general societal trend and incorporated it into their work. The courses met with an increasing resonance, which in turn led to a stabilization and expansion of this offer. In addition, the actors began to network. The result was a perception, recognition and further promotion at diocesan level.

Churches, Religions and Christians for Future
Inspired by Fridays for Future, several ecumenical support networks were founded within the Christian Churches, which shows that nature conservation in the sense of preserving creation is an intrinsic mission of Christians. In Austria, the association is called "Religions for Future"; in Germany, individual Christians gather under the slogan "Christians for Future", while church institutions work together in the Ecumenical Network Climate Justice, also called "Churches for Future", which is also established in Switzerland [109][110][111][112].
Religious organizations were quite quick to join and support the climate movement. One need only think about the biggest church clock in Zurich, at the Church of St. Peter, being stopped at 5 min to 12 during the national climate strike on 28 September 2019 [113].
The Christian climate networks emerged from the belief that the world is created and loved by God. This conviction is firmly anchored in churches' calls to shape the world around the principles of solidarity and sustainability. In Germany, the networks were able to build on existing ecclesial forms of association and action such as the ecumenical cooperation of environmental commissioners. Another important point of reference was the work of church relief organizations such as Misereor or Brot für die Welt (Bread for the World) which, as part of their mission of evangelization, also work to improve people's everyday lives and engage in sustainable development programs. Although their main mission field lies abroad, they also shape the work of churches at home. Swiss associations, such as Brot für alle (Bread for all) and Fastenopfer (Lenten sacrifice), in contrary, do not explicitly point to ecological engagement in their work. For them, the focus has so far been more on traditional humanitarian aid. The emergence of the newest wave of ecological engagement, however, is leading to a shift of consciousness among these organizations and a growing inclusion of ecological issues in their agenda: e.g., the upcoming four Lent campaigns will have an overall focus on ecology and creation care.
The climate networks, which cooperate with non-church groups and initiatives as a matter of course, shape the work of the churches at the diocesan and national level, and at the same time, they receive support, suggestions and assignments from there.

Discussion: The Contribution of the Church to the Implementation of SDG 17
SDG 17-which, as the last goal, reflects on the means of implementation of the SDGs-underlines the importance of cooperation for reaching the intertwined goals of sustainability. In this process, the Catholic Church, like other religious communities, can be an important partner. In this regard, as shown in Section 2, the Catholic Church is not to be seen as a monolithic block but as a community of communities, i.e., of various actors in different places and with multiple practices. They bring in their individual points of view and their specific strengths in initiating or supporting societal change.
The validity of this much broader approach to the Catholic Church was shown in the behavior of Catholic actors in niches, as explored above. In these somewhat protected settings that have rarely been considered in recent studies, new ways of thinking, of imagining, of acting, of socializing or of teaching can be tried out [96]. In these places, actors within the Catholic Church can catalyze change by using diverse assets. The second part of this chapter summarizes the Church's various potentials to act as an agent of change and relates them to the findings of the article.

The Significance of the Transformation-Theoretical Concept of the Niche for the Analysis of the Church's Environmental Commitment
Religions play an important role in shaping society. They can have a conservative and preserving effect as well as initiating and forcing change. In order to grasp this adequately, it is necessary to consider each religious player in its specific role as an agent of change. Therefore, the present article is focusing on the Catholic Church in Germany, Austria and Switzerland.
The Catholic Church is diverse in itself. It is a community of communities. Differences arise from local roots, social compositions, spiritual orientations and thematic foci. It would, therefore, be insufficient to look exclusively to the hierarchical apex, i.e., the statements of the pope or the bishops. Within Church communication, impulses emanate from individual actors who perform as pioneers in niches, regardless of their hierarchical level.
In the field of environmental protection, quite a few Church initiatives became active early on, but with a locally, socially or thematically limited scope. They were initially met with much incomprehension, and skepticism towards environmental discourse still exists today. Difficulties especially arise when it comes to the application of environmental measures on a general level, i.e., the regime level. To face this challenge, numerous initiatives, actions and groups support each other and cooperate. What is more: Since the beginning, and to an increasing degree, they have networked with movements and groups outside the church, which enables them to draw on additional resources and generate a bigger resonance. Through this cooperation, as well as through activities and statements within the church and in the public sphere, church actors are able to support, critically accompany or even advance the sustainability transformation of society.
The causes and motivations behind the Church's environmental initiatives are manifold and still need to be examined in detail. Often, they emerged from religious One World groups and activities in the area of "mission, development, and peace". Concrete causes, e.g., renovations or local renaturation projects, also have an impact. On a more fundamental basis, theology has increasingly been concerned with ecological issues since the 1970s. The aim has been to develop an understanding of creation that harmonizes with the current situation and with contemporary scientific paradigms and developments. These theological approaches to ecological issues are often summarized under the term "ecotheology". An apologetic concern, such as a defense against accusations-which were sometimes formulated in the wake of L. White's essay-is not in the foreground, although these ideas are also reflected upon [19,29,30,57,[114][115][116][117][118][119][120][121][122]. In the religion and ecology research, these efforts have been interpreted as leading to a "greening" of religions, suggesting that religions discuss ecological issues and often become more environmentally friendly over time. Contributions from this field of research have analyzed this "green turn" and highlighted rather the potentials [4,5,90,[123][124][125][126][127][128] or the limits [95,[129][130][131] of religions to address environmental problems from different perspectives.
The Church's ecological commitment must be seen and understood as part of a process of development in society as a whole. In it, the Christian creation faith takes on a contemporary form. From a theological point of view, the Church's environmental awareness is not a foreign body in the Christian world of thought, not an idea coming "from outside" that first has to be "baptized". Even if considerable learning is still needed in the Christian factual understanding of creation, it is theologically misleading to distinguish between Christian and ecological explanations in ecclesiastical environmental activities. Rather, the two enter into an inseparable connection that can be captured by terms such as creation faith or creation spirituality.
Niche actors within Church environmental communication can appear in different places as well as different forms. In other communication contexts, they may occupy a different position and belong to the regime level. Thus, the status does not depend on the actor, but on the actor's position in the respective discourse.

The Catholic Church's Potentials to Promote Societal Change
The Catholic Church supports climate action and sustainable development with many initiatives and in many places. Its potential to contribute to societal change, which was exemplified and explored in the case studies above, can be summarized by the following six interrelated aspects: 1.
The Catholic Church has community-building effects. Members seem not to be strangers to one another. In this way, the Church can foster an attitude of international and intergenerational solidarity that is based on spiritual and emotional affects and thus can influence people's actions much more strongly than rational calculations could.

2.
The Church combines its universality (the literal meaning of "catholic") and globalism with the fact that it is inevitably rooted in localities. It is the community of the local communities of believers. Therefore, in its fundamental self-understanding, it shares a common trait with sustainability: combining the local and the global [132].

3.
The Church's environmental engagement is theologically inspired by two central ideas. It strongly emphasizes the unity of the "human family" and combines this idea with the "option for the poor, the weak and the neglected"-which nowadays encompasses nature, too. This principle was originally developed as part of the "theology of liberation" [19,133] and officially articulated by the Catholic Bishops of Latin America (CELAM) at influential conferences in Medellín (1968) and Puebla (1979) [134,135]. Some of the core values of Christian moral teaching such as human dignity, recognition, compassion and justice are the same as those taken as fundamental in the sustainability program. 4.
The Church, like any major religion, offers an all-encompassing worldview. It addresses, as shown in the encyclical letter Laudato si' [45], questions of life and death and proposes sound attempts at understanding the meaning of life. It interrogates humanity's role in the era of the Anthropocene. On the one hand, this era is seen as the consequence of emerging problems of human power that have overwhelmed not only natural forces but also human understanding, scientific insights and foresights and social responsibility [136]. On the other hand, it calls forth a planetary stewardship, which seems to make it necessary to unify all human powers and skills [137]. A moral guideline for these changes can be the aforementioned option for the poor, the weak and the neglected. 5.
The Church as an agent of change can rely on its multidimensional approach. In contrast to scientific studies like the IPCC reports, religions address not only the cognitive dimension but also the spiritual, emotional, social and habitudinal dimensions, e.g., in religious services, rituals, prayers or narratives. This can be done in very different ways as the examples of Creation Time, car fasting or environmental education have shown. This multidimensional approach is an important factor for transformation because the necessary motivation for societal change will not be engendered by pure information but by touching the emotions, by changing the "habits of the heart" [138]. 6.
It is not only the faithful, the members, who can and do act as individuals, but also various ecclesiastical organizations like parishes, dioceses, orders or welfare organizations that can have an influence on sustainability, e.g., by pursuing sustainable procurement. In addition, the Holy See is a subject of international law and has the status of a "permanent observer" in the system of the UN, which is unique in the religious sphere and which gives the Catholic Church a special ability to act. Unlike many other institutions, but of course not all of them, the ecclesiastical institutions have an intrinsic motivation. It comes from the Christian Gospel to read in a prophetic way the "signs of the times", i.e., to be in a spiritual-that is, a realistic, yet hopefulway, aware of oncoming changes that can threaten the common good [40]. At the same time, this approach offers an opportunity for reshaping (global) society in order to make the world a better place for all people and for all living beings.
These six strengths and competences, which can also be found in different forms in other religious communities, enable the Church to act in a specific way as a "transmission belt" for the SDGs [3].

Conclusions
Society is facing the challenge of global warming and other ecological risks that require profound and lasting societal change. Such great transformation can happen when overarching trends create pressure and individual groups simultaneously develop suitable alternatives. Like other societal groups, religious communities can drive change [4][5][6][7][8][11][12][13][14][139][140][141] (pp. [63][64][65][66]. To explore this in detail, this article focused on the ecological commitment and climate action of the Catholic Church in German-speaking countries. The starting point of this study was the understanding of the Church as a community of communities or a multi-layered actor, which is a point of convergence between ecclesiology and the sociology of the church [142][143][144][145][146][147][148]. Hence, instead of reducing the analyses of the Catholic Church's environmental activities to its hierarchical apex-as is often the case in greeningof-religion research, which fails to address many important phenomena-it considered in a differentiated way the plurality and particularities of ecclesial actors in order to realize a comprehensive sketch of these measures.
By exploring several case studies with the help of the transformation-theoretical multilevel approach of Geels et al. [72,73], it became clear that the concept of the pioneer or niche actor has to be understood in a purely analytical way. A niche can be spatially, socially or thematically constituted. It is functionally related to the transformation process in question. This means that actions or expressions of the actor in question in other spatial, social or thematic contexts can also be assigned to the mainstream. With this perspective, it can be more easily grasped that even members of the organizational leadership cannot simply enforce new ideas by decree but act as pioneers in the transformation-theoretical sense.
From a theological-ethical perspective, the form of social change is relevant in addition to the goal. The cooperation of the transformation actors should take place according to the principle of subsidiarity, i.e., as cooperatively as possible and as close as possible to the location of the problem. More research has yet to be done to explore the role of this principle as a change-supportive factor in the Church as an influential actor in the transition to a sustainable society.