This book examines the life, work, and thought of Palladius of Helenopolis (ca. 362‰ÛÒ420), an important witness of late antique Christianity and author of the Dialogue on the Life of St. John Chrysostom and the Lausiac History. These compositions provide rich information concerning the downfall of John Chrysostom, the Origenist controversy, and many notable personalities such as John Chrysostom, Theophilus of Alexandria, Jerome, Evagrius of Pontus, and Melania the Elder. The book examines Palladius' role as an advocate on behalf of John Chrysostom, and it employs late antique theories of judicial rhetoric and argumentation (issue or stasis theory), the significance of which is only now becoming apparent to late antique scholars, and elicits new insights from the Dialogue regarding the controversy that resulted in the death of John Chrysostom. The book also demonstrates that the Lausiac History promoted to the imperial court of Pulcheria the ascetic practices of his ascetic colleagues, whom Jerome had recently decried as Origenists. The book delineates Palladius' understanding of asceticism, Scripture, contemplation, prayer, human freedom, and theodicy to demonstrate a dependence upon the spirituality of his mentor Evagrius of Pontus, and upon the broader theological legacy of Origen. What emerges from these pages is the self‰ېportrait, rather than a polemicist's caricature, of an Origenist at the turn of the fifth‰ېcentury, who has profoundly influenced Christian history, hagiography, and piety for nearly 1,600 years.