The aim of the present work is to determine the scientific tenor of the sociology of religion through a reflection on its method and that of its sources. To these ends and in order to honor its birth, “Protestant Ethics and the Spirit of Capitalism” – its foundational stone – has been chosen as the work to be analyzed. This requires a brief introduction about the concept of science – its implications and its derivations – as well as a brief description of the historical circumstance in which the production of the work under analysis took place. In the end, the study of its episteme will be developed, arriving in a timely manner to the partial and definitive conclusions.