The article raises the question of how the multiplication of topics, turns, and perspectives in the currents of the study of religions can be explained. After the concept of a paradigm shift (Thomas Kuhn) is introduced, the study examines the epistemological consequences of the question What is religion? It is based on analyzing the practice of defining “religion” in German-language encyclopedias of the past three centuries. Surprisingly, the structure of these articles is largely persistent throughout this long period and consists mainly of etymology, definition (Wesensbestimmung), and a typology of “religion.” From this, an Aristotelian paradigm can be deduced. The claim for universality entailed in this paradigm ultimately led to a crisis and since the 1960s the study of religions has developed alternative approaches that emphasize aspects of human interaction, communication, and reciprocal relationships. I propose to subsume these new perspectives under the term “a relational paradigm.” Examples and consequences for this paradigm are offered in the conclusion.