The thesis that socialism and communism have some traits in com‑ mon with religion has often been argued for. Here we analyze the well‑known positions of A.V. Lunacharsky on religion, which he developed in close connection with Gorky’s God‑building, and A.A. Bogdanov’s critique of religion and religious language as a form of authoritarian ideology. Their opposite views on religion were formulated within the same context, where revolution, for both of them, had to invest not only the political structures, but also the ways of thinking and feeling, of making sense of life and death. While for Lunacharsky the faith in the collective and the drive toward happiness for all should be expressed in a religious form, according to Bogdanov socialism has to be a “scientific” conception of the world. After 1917 both thinkers reasserted the importance, respectively, of feelings and passions, as well as of a new “proletarian” science.