According to Gianni Vattimo, the secularization process can be seen as analogous to the “death of God” in the Western world. The “weak theology” that results from that view will be used in the article as a starting point for the study of three 19th century authors, lay and religious at the same time, Pierre Leroux, Edgar Quinet and Ernest Renan, who reflect on the meaning of religion in the modern world, as well as on its relation with the democratic State.