Some fifty years ago scholars claimed the end of religion was nigh. Modernity and postmodernity presumed the eclipse of religion. However, religion persists, in diverse forms and expressions, yet not without some considerable problems. Why is religion so persistent? And what of contemporary problematic issues, such as extremism and terrorism, often associated with religion? In this exploratory article, which began life as the Presidential Lecture to the 2012 AASR conference, held in conjunction with the Australian Association for Buddhist Studies, I suggest some reasons that might help explain the persistence of religion, and I discuss the contemporary key problem of an adequate conceptual mechanism for coping with religious diversity. Continuity and diversity are twin features of religion that challenge the modern world. If modernity must contend with the persistence of religion, then contending with diversity is, perhaps, the chief religious issue underlying the problem of exclusivist extremism.