The present work is the doctoral thesis of J.-B. Chabot (1860-1947), who studied under Lamy and would go on to publish and translate many other Syriac texts. This volume is concerned with the life and work of the widely influential Church of the East author Isaac of Nineveh (late 7th cent.), part of whose writings would eventually reach many other languages and churches. Chabot discusses the available data for Isaac’s life, orthodoxy, writings, and ascetic system; the final part includes extracts from his works with Latin translation. The book is concluded with the Syriac text and Latin translations of three of Isaac’s sermons edited from British Museum manuscripts. This groundbreaking work on an important author in the Syriac tradition continues to merit study.