Research Center for Biographical Studies in Contemporary Religion

In the Research Center for Biographical Studies in Contemporary Religion, we have conducted empirical research projects for more than two decades concerning a variety of themes, religious preferences, and age groups. The analysis of children’s drawings, youth, magic and religion, the study of mediation of conflicts in the classroom, and an interview study for the Enquête Commission of the German parliament about members and deconverts from Christian-fundamentalist groups were part of the earlier research, while major third-party funded research included the Study on Deconversion (2002-2005) and the Study on the Semantics and Psychology of Spirituality in USA and Germany (2009-2012), and a Study of Xenosophia and Religion in Germany (2011-2015). These projects were generously funded by either the German Research Foundation (DFG) or John Templeton Foundation—or both by matching funds. Results were primarily published in books that include also a large number of case studies.

In the research projects on deconversion, spirituality, and xenosophia, we administered the faith development interview (FDI) to a selection of the sample; and, while a much higher number participated in the survey, we have always invited FDI interviewees to also answer the questionnaire. Thus, in regard to methods, we used a combination, or triangulation, of quantitative research strategies with qualitative methods based on biographical interviews—and the FDI is a great invitation to biographical narrating. Teams both at Bielefeld University and the University of Tennessee at Chattanooga dedicated time and energy in bringing this research forward over two decades.

Since 2014, we have turned to a longitudinal investigation and reached out to previous interviewees to invite them to a second, third or even fourth participation in the FDI and the questionnaire. This results in a database of more than 1,500 FDI transcripts and more than 6,600 questionnaire participants. The 2026 book, Styles of Faith (see announcement and link in the column on the right-hand side), includes not only our current state of the theory of faith development, but also brief summaries of findings. A brief summary and many links to our publications can also be found in the Report to the DFG.

Our research interest in faith development originates in the theoretical and methodological engagement with James Fowler's faith development theory and research. However, our approach aims at better accounting for the complexity and variance of faith development—including progression and regression—and thus is not based on the assumption of mono-directional, stage-wise development. The discussion and revision of the theoretical framework of faith development theory resulted in a model of faith styles that is also presented in the 2026 book.