This introductory chapter gives an overview of the intricate relation between Heidegger and theology. Firstly, it discusses Heidegger's indebtedness to theology by revisiting the debate that was initiated by the publication of his early Freiburg lectures in the 1990s. Second, it sketches in broad strokes the reception history of Heidegger's works within twentieth-century theology. In the third and final part, the implication of the new facts revealed by the Black Notebooks are discussed. By revisiting Hans Jonas's lecture "Heidegger and Theology", delivered at Drew University in 1964, the author indicates how Jonas already in the 1960s revealed the potential shortcomings of a theology that takes its basics tenets from Heidegger's philosophy.