“Summas” and systematization
Steven Ozment notes, “Before the Ockhamists made Pelagianism a major issue in medieval theology, the scholastic debate over religious justification focused on how grace could be present in man’s soul. How can something divine be within human nature? If medieval philosophers had problems conceiving existence of a universal within a particular, there were even greater difficulties for theologians who tried to imagine godly purity within a finite sinful creature” (“The Age of Reform, 1250-1550: An Intellectual and Religious History of Late Medieval and Reformation Europe”, New Haven and London: Yale University Press, ©1980, pg. 31).
There were different schools of thought, and the early Medievals, especially, began to wrestle with these questions, they “moved to codify” the discussion of theology, at the heart of which was the doctrine of God.
Following up on some of the “developing questions” that he outlined, Richard Muller mentions that the natural urge of these writers was to explore fully and to systematize their thoughts.
The next major stage in the formulation of the medieval doctrine of God appears in the work of the various writers of “summas” and books of “sentences”: in the mid-twelfth century, Honorius of Autun, Hugh of St. Victor, Peter of Poitiers, Robert Pulleyn, Alain of Lille, and Peter Lombard moved to codify the topical discussion of theology (as distinct from the running commentary or “gloss”) into a separate course of study.
Whereas Hugh of St. Victor’s De sacramentis and Summa sententiarum adopted a fundamentally neo-platonic approach to the doctrine of God and world, understanding the creation as an emanation of being out of God and developing his doctrine of God by way of God’s self-manifestation in creation and redemption, Lombard’s Sentences begins with the doctrine of God, returning to the Anselmic sense of God as the primary object of theology but with far fewer Platonic or neoplatonic emphases than either Anselm or Hugh.
Where Lombard differs methodologically from several of his most important predecessors, like Anselm and Hugh, is in his emphasis on the rootage of doctrine directly in Scripture and the fathers: his work stands as a theological textbook that emphasizes the sources of theology and derives all discourse from them rather than develop a more speculative or philosophical approach to the materials. This methodological difference may also account for a difference in order of discussion: Lombard departs from the method of Anselm by beginning his doctrine of God with the doctrine of the Trinity and the discussion of concepts of essence and attributes folding into the discourse as a whole.
In Lombard’s model, the Augustinian distinction between sign and thing, signum and res, provided the argumentative shape for the entirety of his theological presentation in the Sentences. The result of this approach was, among other things, the integration of theological and philosophical questions in the doctrine of God, the understanding of God as the ultimate reality (summa res) and the fruition of all things, and, therefore, of the doctrine of God as the foundational statement and interpretive key for all subsequent theological discourse.
Muller, R. A. (2003). Post-Reformation Reformed Dogmatics: The Rise And Development Of Reformed Orthodoxy; Volume 3: The Divine Essence And Attributes (pp. 37–38). Grand Rapids, MI: Baker Academic.