This work interprets fourth-century theological discourse as an incident in the history of masculine gender, arguing that Nicene trinitarian doctrine is a crucial site not only for theological innovation but also for reimagining and reproducing manhood in the late Roman period.W hen the Trinity became for the first time the sine qua non of doctrinal orthodoxy, masculinity was conceived anew, in terms that heightened the claims of patriarchal authority while cutting manhood loose from its traditional fleshly and familial moorings.;In exploring the significance of this late antique movement for the subsequent history of ideals of manhood in the West, this study directly engages, combines, and thereby disrupts the divergent disciplinary perspectives of historical theology, late Roman cultural history, and French feminist theory. The author brings contemporary theorist Luce Irigaray into dialogue with the Patristic corpus to coax out a fresh interpretation of ancient texts and themes.