In this letter, St. Anselm expresses his humility and reluctance to defend the Christian faith, which he believes stands firm without his support. He addresses a cleric's troubling assertion that all three persons of the Trinity are incarnate, a claim attributed to the late Archbishop Lanfranc. Anselm firmly denies this notion, emphasizing that he has never entertained such ideas and that any assertion contrary to the orthodox understanding of the Trinity is anathema. His letter serves as both a defense of his own beliefs and a clarification of the true nature of the Trinity.