This book deals with the question of whether religious worldviews fulfil an explanatory function in the lives of believers. After rebutting some common objections to this claim, the author proposes to understand the explanatory nature of religious belief along the lines of inference to the best explanation. This proposal is qualified in view of the peculiar nature of religious belief: It is stressed that the type of explanation concerned occurs within the bounds of religion alone, and loses its sense apart from the religious form of life. In unfolding his argument, the author draws heavily on ideas of explanation developed in the philosophy of science, pointing to differences and comparisons between religious and scientific explanations. The author concludes by considering some specific things that theism explains.