In the last two decades, the question of religion has become a central concern of many philosophers belonging to the Continental philosophical tradition. As the interest in religion has grown within Continental philosophy, so also has the question of Martin Heidegger’s relationship with religion. This paper poses the question of what religion meant to Martin Heidegger in the development of phenomenology as ontology; how he preconceived the notion of religion and why he eventually denied any authenticity to religion. In engaging with this question, the paper will also attempt to disclose some delimitations of Heidegger’s approach to religion.