How is it possible to increase knowledge in theology?

This paper is devoted to the question, is it possible to increase knowledge in the field of theology like as it is possible in humanities in general. The main difficulties first of all consist in (1) confessional character of each theology, (2) in its plurality when each theology has its own concept system and original epistemological framework, (3) in the resulting incomparability of theologies. Discussing the presumably scientific character of theology, it could be useful to discern between premodern and modern understanding of the term “science”. The author argues, there do not exist insurmountable obstacles for theology to strengthen its argumentative basis, namely, theology possesses opportunity to get closer to the human sciences if it relies on empirical researches, for instance, of psychology of religion. This thesis is illustrated on two different examples from different regions and contexts: the theory of structure of religious experience by K. Girgensohn and W. Gruehn, and the theory of political aspect of religious conversion by I. Martín-Baró. The both theologies base their generalization on correct empirical research data, — like it occurs in philosophy of religion or even human sciences. The both cases demonstrate increase of knowledge: the first on from which elements does religious experience consist and how it is developing; the second on how religious conversion is tied to change of political views and social behavior of believers. Such contact of theology with empirical science of religion is in no way harmful for the both sides; it can be initiated in various traditions, which adopt the focus of broadly understood Western-born rationality.