The identification and publication of an ancient Armenian translation of Eusebius of Emesa's Commentary on Genesis (1980) and the edition of fragments of his work in the Greek Catena in Genesim have opened new perspectives for the study of this fourth-century scholar and bishop of Syrian descent. This book now brings together the evidence of the various branches of tradition of this work, the oldest complete Antiochene commentary to survive. The author concentrates on one of the most striking characteristics of Eusebius' commentary: its interest in translation problems and appeal to alternative readings. Apart from the Septuagint, the version commented on, Eusebius quotes "the Syrian" (ho Syros) and "the Hebrew" (ho Hebraios). It has long been unclear what or who answered to these names. The author proposes a new solution to this problem. The first part of this study deals with the content and affiliations of all biblical quotations in the Commentary, and with their place in Eusebius' method of exegesis. The author demonstrates that Eusebius refered to the Hebrew and Syriac texts in their original languages. He had direct access to the Syriac text (and is thus one of the oldest witnesses to the Peshitta version), but used informants for his knowledge of the Hebrew text. His approach in assessing the value of the different versions of the biblical text is contrasted with that of his predecessors Origen and Eusebius of Caesarea, his contemporary Jerome, and later Antiochene exegetes who followed or criticized him. The second part gives the basis of the first: it is a collection of all passages that cite alternative readings. All texts are given in their original languages and in English translation. A commentary deals with the textual tradition of each passage, identifies the questions Eusebius wanted to solve by the use of alternative readings, contrasts his handling of the text with that of others, establishes his sources, and studies the biblical quotations in detail.