It is obvious, if we consider Trinitarian language, that we are stretching the capabilities of human reason and also language. God’s begetting of the Son is indescribable or “ineffable.” Just as the Son’s “generation according to the flesh differs from all others – for where among men do you know of a virgin mother? – so does he differ also in his spiritual generation. Or rather he, whose existence is not the same as ours, differs from us also in his generation.

“Who, then, is that Father who had no beginning?” Gregory asks. Well, for one thing, he is a father unlike any other. For while other fathers must first be born, grow into maturity and then father children, this Father has always been a Father. It is his nature to be Father, to generate the Son and to emit, spirate or breath the Spirit. In addition, the Father is Father as distinct from the Son. He is neither the Son nor the Spirit, just as the Son and Spirit are not the Father. While a human may occasionally function as a father or a son, within the wonder of trinitatian relationships, the Father is Father in an absolute sense, as is the Son as Son and the Spirit as Spirit. Thus the fatherhood of God, while occasionally analogous to human fatherhood, is utterly unique.
Gregory rebukes the tendency in all of us to reject that which we cannot comprehend. Gregory’s theological opponents insist, for instance, that the Son could not be “begotten,” because such a generation fits no reasonable categories. Part of the problem, Gregory responds, is that the model these theologians use to picture the divine generation is itself faulty.

Gregory first advises that we must cast away any notions of flow or concepts of immaterial as if it were material birth and then we may perhaps worthily conceive of the divine generation. And what is a worthy conception of such a mysterious generation? Who can say? “The begetting of God must be honored by silence. It is a great thing for you to learn that he was begotten. But the manner of his generation we will not admit that even angels can conceive, much less you.” Only the Father, Son and Spirit could possibly comprehend it. “It was in a manner known to the father who begot, and to the Son who was begotten. Anything more that this is hidden.