Abstract: In the later years of the fourth century the monk Jovinian was condemned at Rome and Milan for teaching that all baptized Christians were equal in God's sight and that all would receive an equal reward in heaven regardless of ascetic merit. This book is the first study in English devoted to Jovinian and the controversy sparked by his teaching. In chapter 1 I offer a reconstruction of Jovinian's teaching, uncovering its strong anti-heretical emphases, exposing its biblical foundations, and relating it to fourth-century baptismal practice. Subsequent chapters place Jovinian in a variety of contexts: the rise of a Christian aristocracy in the fourth century (chapter 2); the development of an anti-heretical tradition in the first three centuries (chapter 3); the proliferation of this heresiological discourse in the fourth century (chapter 4); and the history of Marian theology, especially on the matter of Mary's perpetual virginity (chapter 5). In the final two chapters I distinguish the different approaches to marriage, celibacy, and clerical life evinced by Jovinian's opponents (chapter 6), and highlight the ways in which one of these opponents, Jerome, became the object of criticism and accusations of heresy. If there is a single conclusion to be drawn from this study, it is that Jovinian stood much closer to the mainstream of the Christian tradition than previous critics (including his ancient opponents) allowed.

Keywords: Jovinian, marriage, celibacy, orthodoxy, heresy, virginity, Augustine, Ambrose, Jerome, Siricius