This is a commentary composed by the Irish monk Sedulius. It discusses Saint Jerome's significant undertaking of translating and correcting the Gospels from Greek into Latin at the behest of Pope Damasus. Jerome highlights the discrepancies found in various Latin versions of the Gospels and emphasizes the necessity of relying on authentic Greek manuscripts to produce a reliable translation. He acknowledges the challenges of this task, particularly the potential criticism from scholars and the general public regarding his work. The text delves into the differences between codices and exemplars and the implications of altering established language and interpretations within the Christian community.