The Incarnation and Resurrection transformed the perception of this background in fundamental ways. God became man, so that divinity and humanity could now intermingle; also, the world was no longer eternal, nor was it divine–it had a beginning in time; and, perhaps most significantly, the doctrine of grace would reshape man’s relationship with God in entirely new ways. Our entire background picture, how we mentally and unconsciously represent the world, was, if not turned upside down, at least radically transformed (2), and so was our society. For example, all men are now essentially brothers, poverty is elevated as an ideal, charity is materialized by hospitals and the abolition of gladiatorship, and so on.
This is why philosophy could ultimately be integrated into Christian theology: philosophy is a discourse that brings man to the understanding of what exists, as we said earlier. God as Father, Son, and Holy Spirit is what exists; philosophical discourse, as a tool of reason, can therefore be used to grasp the essential concepts of this truth. This the Greek fathers of the Church understood, and made abundant use of philosophy to comprehend the new condition of existence without altering the essential truths of Revelation. Rather, it is the older conceptual terms that were changed or took on new meanings. Hence, the older notion of monad was no longer tenable to describe God; the new notion of Trinity required the introduction of new terms (hypostasis) unknown in this meaning to pre-Christian philosophy. The distinction between essence (ousia) and energy (energeia) also became fundamental to comprehend the new reality. There are two implications to this:
First, Christian revelation did not destroy philosophy as a discipline. Ancient philosophy was not a discipline whose tenets were immutable and unchangeable, since philosophy is not truth, but a questionning to arrive at truth. It is not because the ancient philosophers did not think the world to have a beginning in time, that we should reject Christian revelation as either un-Greek or false. Philosophy is not a dogma; its conclusions and arguments can be changed, re-interpreted, and can even be surpassed. When it encounters the Trinity, philosophy becomes theology; yet, it retains its speculative flavor (What is the relationship between the Father, Son, and Holy Ghost? How is union of man with God achieved? What are the steps to its realization?…). This is why, on the other hand, the only valid ground to theology is an intimate relationship with the Triune God–praying. Only by knowing Who the Trinity is is it possible to theologize and thus philosophize (“If you pray, you are a theologian; if you are a theologian, you pray truly”, said St. Neilos).
The other implication is that when Christian revelation encountered the Graeco-Roman world, especially its educated members, far from being corrupted into something else, it embraced its culture, permeatted it, and, in many ways, renewed it. But never was the Christian message tainted by philosophy, since it is the very nature of philosophy to adapt to its object of study. We may call to mind the Cappadocian Fathers, and especially the two Gregories, or again Maximus the Confessor, who all made abundant use of philosophy to describe the mystery of Christ. When Christianity encountered Greek culture, it was understood by the Greek-speaking people in a Greek way; and since Greek culture had long been the dominant cultural force in the Mediterranean, it was all too normal that it should once again play this role with the new faith. Likewise Christianity would put on Roman clothes among the Romans, Slavic ones among the Slavs, Ethiopian among the Ethiopians, and so on, without the essential truth being corrupted by the encounter itself.