No account of James's religious views would be complete without a discussion of his 1902 Gifford Lectures, The Varieties of Religious Experience: A Study in Human Nature (1902). A groundbreaking work in both the psychology and the philosophy of religion, Varieties is widely and credibly regarded as James's most accomplished and influential work on the subject of religion. What is seldom appreciated, though, is that James's “study in human nature” also represents one of the major sources for his moral views, including his views on such important issues as the metaphysics of morals, moral psychology, and the nature of human flourishing. This chapter shows that, in addition to his primary aim of demonstrating the unique practical value of religion using empirical methods, and his secondary (but no less important) aim of offering a credible supernaturalist interpretation of religion, James also discusses a number of important issues in ethics in Varieties and comes to modify some of his earlier moral views in the process of developing a realistic and pluralistic account of religion. Some of the most important changes to be found in James's moral views, as we shall see, are occasioned by changes in his religious views, specifically his views on (1) the morally transformative capacity of religious experience, (2) the possibility of religious knowledge through religious experience, and (3) his views on the source and ground of our moral ideals.