I ran across this nice short description of the Trinitarian theology of the Cappadocian fathers. This can be an intimidating subject loaded with complexities and dense jargon. But these paragraphs accurately distill the essence of the teaching on the Trinity. The writer, David Hart, makes the point that Trinitarian doctrine is nothing other than the language of salvation.
I took this from the latest issue of First Things.
The article is entitled, “The Lively God of Robert Jenson.”
The greatest achievements of this period, in defense of Nicene orthodoxy, were those of the so-called Capppadocian fathers: Basil of Caesarea, Basil's younger brother Gregory of Nyssa, and Basil's friend Gregory of Nazianzus ….
It must be appreciated, I hasten to add, that "salvation " was not understood by the Cappadocian fathers in that rather feeble and formal way many Christians have habitually thought of it at various periods in the Church's history: as some sort of forensic exoneration accompanied by a ticket of entry into an Elysian aftermath of sun-soaked meadows and old friends and consummate natural beatitude.
Rather, salvation meant nothing less than being joined to the living God by the mediation of the God-man Himself, brought into living contact with the transfiguring glory of the divine nature, made indeed partakers of the divine nature itself (2 Peter 1 :4) and co-heirs of the Kingdom of God. In short, to be saved was-is-to be "divinized" in Christ by the Spirit. In the great formula of St. Irenaeus (and others), "God became man that man might become god."
It is precisely here, therefore, in the economy of salvation, that the true nature of the eternal Trinity must declare itself-for, simply said, no creature could ever join us to God. The calculus of the infinite is absolute: The finite can never reach the infinite, the created can never aspire to its transcendent source, and nothingno economically reduced manifestation of the Godhead, no "ontological pleonasm" of mediating principIes, no conceptual Tower of Babel erected upon the foundations of the human spirit-can unite us with God save that God in His mercy condescend to unite us to Himself, by becoming one of us.
If the Son saves us by joining us to the Father, then the Son must necessarily be, in every sense, God of God, essentially and infinitely. But, then again, how are we joined to the Son? By the Holy Spirit-in the sacraments and corporate life of the Church and in His sanctifying work within the soul and so the Spirit too, it follows, must be God of God, no less than the Son. Only God can join us to God, and so we must affirm that in the incarnation of the Son and actions of the Spirit God Himself is in our midst.
Or rather, more wonderfully, we are in the midst of God, and the movement of relation among the three divine Persons, as it is unfolded through salvation history, is nothing less than the triune God drawing us into the infinite splendor of His life.