The Proslogion (Latin Proslogium; English translation, Discourse on the Existence of God), written in 1077-1078, was written as a prayer, or meditation, by the medieval cleric Anselm which serves to reflect on the attributes of God and endeavours to explain how God can have qualities which often seem contradictory. In the course of this meditation, the first known formulations of the ontological argument for the existence of God was set out.

Cur Deus Homo? (Why God Man?) is a book written by Anselm of Canterbury in the period of 1094-1098. In this work he proposes the satisfaction view of the atonement. Anselm says his reason for writing the book is: I have been often and most earnestly requested by many, both personally and by letter, that I would hand down in writing the proofs of a certain doctrine of our faith, which I am accustomed to give to inquirers; for they say that these proofs gratify them, and are considered sufficient. This they ask, not for the sake of attaining to faith by means of reason, but that they may be gladdened by understanding and meditating on those things which they believe; and that, as far as possible, they may be always ready to convince any one who demands of them a reason of that hope which is in us.

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.

This Anglo-Latin work explores the theological debate between the Greek and Latin Christian traditions concerning the procession of the Holy Spirit. While the Greeks reject the Latin view that the Holy Spirit proceeds from the Son, they share core beliefs about the nature of God as a perfect unity of Father, Son, and Holy Spirit. The author seeks to engage in this discourse with humility and a commitment to truth, using the Greeks' own beliefs as a foundation for understanding their position. The distinctions between the roles of the Father, Son, and Holy Spirit are clarified, emphasizing their unity and distinctiveness within the Trinity.

This work by St. Anselm explores theological concepts surrounding the nature of good and evil, particularly in the context of angels and their free will. It argues that all beings receive their essence from God, who is the source of all goodness. The text examines why the devil fell, suggesting that he lacked perseverance because it was not granted by God. It also delves into the nature of justice and injustice, the reasons behind the inability of fallen angels to return to righteousness, and the inherent goodness of the will. Ultimately, it asserts that evil is the absence of good, rather than a tangible entity.

In 1102, a council of bishops and abbots was convened in London under the leadership of Archbishop Anselm of Canterbury. This assembly aimed to restore ecclesiastical discipline and address various issues that had arisen due to moral decay within the church. The council condemned simony, mandated appropriate vestments for clergy, and established numerous regulations regarding the conduct of clerics, marriage restrictions, and church governance. The reforms were intended to strengthen the Christian faith in England and ensure that church practices aligned with religious principles.