Religious thought and spirituality can be considered as a part of natural human capacities. There is an exponential rise in clinical research in the relationship between religion, spirituality and positive health outcomes. Most of these studies, however, have been primarily descriptive, rather than explanatory, focusing on identifying their underlying mechanisms. Almost no attempts have been made to find novel methods to mirror and monitor positive, and possibly negative, reactions related to the local and general effects of religion and spirituality in healthy subjects and patients. As this area of interest is rather new, we propose to put forward a new hypothesis that effects of religion and spirituality can be objectively studied by various exhaled biomarkers, some of which have already been developed and tested in health and disease. The lungs are particularly well suited for this purpose, as we have easy access to exhaled air and thereby a possibility to develop methods that measure compounds directly released from them. This work is the first step in the convergence of medical and theological research by linking various biomarkers and physiological measures with indicators of individual belief systems, religiosity and spirituality.