This monograph encompasses the first critical edition, translation, and historical study of a series of lectures from the cathedral school of No-tre-Dame, Peter Comestor's Glosses on the Glossed Gospel of John. Deliv-ered in Paris in the mid-1150s, Comestor's expansive lecture course on the Glossa ordinaria on the Gospel of John has survived in no fewer than seventeen manuscript witnesses, being preserved in the form of contin-uous transcripts taken in shorthand by a student-reporter (reportationes). The editor has selected the fifteen best witnesses to produce a critical edition and translation of the first chapter of Comestor's lectures on the Gospel of John. In addition to the text of the original lectures, the edition includes appendices containing accretions to the lecture materials added by Comestor and his students, as well as the corresponding text of the Glossa ordinaria from which Comestor lectured. The Latin text and translation of Peter Comestor's lectures are pre-ceded by a wide-ranging critical study of the historical and intellectual context of Peter Comestor's biblical teaching. This study begins with an outline of Comestor's scholastic career and known works, with a detailed introduction to his Gospel lectures and the relevant historiography. Sub-sequently, a survey is made of the intellectual landscape of Comestor's lectures: namely, the tradition of biblical teaching originating at the School of Laon, preserved in the Glossa ordinaria, and developed in the classroom by Peter Lombard and a succession of Parisian masters, nota-bly Comestor himself. The following section examines the portion of the lectures presented in this book, encompassing an overview of its contents and structure, a description of Comestor's teaching method and scholas-tic setting, a study of the text's sources, and a consideration of Comestor's participation and reception in the scholastic tradition. The final chapters contain a careful description of the manuscripts and editorial principles adopted in the Latin edition and translation.