“Transpose then to the divine dogmas the same principle of differentiation which you acknowledge with regard to substance and hypostasis in our affairs, and you will not go wrong” (EpPet. 3e). Well, I’ve been pretty good at basic grammar ever since Mr Harocopos drilled the rules into me in the eleventh grade, so it’s nice to think that all of that hard work might pay off in the field of trinitarian theology. Elaborating upon the proposal of his brother, St Gregory of Nyssa commends to us two directives by which to speak rightly of the one God in whose triadic Name Christians have been baptized.
1) Attribute equally to the Father, Son, and Spirit that which belongs to the common substance of God. Just keep in mind that the divine ousia is incomprehensible. Gregory writes: “Whatever your thought suggests to you as the Father’s mode of being—for it is idle for the soul to insist on any discrete conception because of the conviction that it is above all conception—you will think also of the Son and likewise of the Holy Spirit” (EpPet. 3e). If God the Father is uncreated, then so are the Son and Spirit; if invisible, impassible, immutable, infinite, omnipotent, then so are the Son and Holy Spirit. All such properties belong to that nature which each of the divine hypostases possesses equally and fully.
2) Attribute to the proper hypostasis that which belongs uniquely to the Father, Son, or Spirit. If the Father is unbegotten, then this quality is to be predicated of him alone and not of the Son and Spirit. If the Son is begotten, then this quality is to be predicated of him alone and not of the Father and Spirit. If the Spirit proceeds from the Father (through the Son?), this quality is to be predicated of him alone and not of the Father and Son. “And since it is necessary that the distinction in the Trinity be kept unconfused by means of the notes of differentiation,” Gregory explains, “we, in our assessment of that which differentiates, shall not adduce what is contemplated in common, as for example the uncreated that I mentioned or what is beyond all comprehension or any such quality. We shall seek only the means by which the conception of each shall be separated lucidly and in an unconfusing manner from that which is contemplated in common” (EpPet. 3e).
What St Gregory is doing, in other words, is theology as grammatical reflection. If we wish to know what ousia and hypostasis mean, we must first attend to how these terms regulate the language of faith. Khaled Anatolios elaborates:
In modern scholarship, the regnant questions regarding Gregory’s appropriation of this linguistic and logical edifice are whether they indicate a merely generic unity that is vulnerable to the charge of tritheism, and what if any content they ascribe to notions of divine personhood and “communion.” While such questions are certainly worthy of treatment, it needs to be asked whether their dominant status in interpretations of Gregory’s use of ousia-hypostasis language is due to a narrowly propositionalistic preconception of trinitarian doctrine. As stated at the outset of this work, one of the principal hermeneutical principles of the approach undertaken here is that doctrines truly signify the realities of divine things not directly and autonomously in their bare propositional form but precisely through the regulation of Christian discourse and action as a whole. This synthesis of effecting an objective reference (the reality of what is signified) and regulating the act of signification is perhaps most clearly evident in the case of ousia-hypostasis language. The evidence for this properly synthetic function of such language becomes manifest as soon as we take account of what happens when we neglect the distinction between these two aspects by which the doctrine achieves its meaning. When Gregory says in this epistle, “We shall not include in our evaluation of the differentiation [which delineates the distinction of hypostaseis] what is seen to be common, such as the attribute …,” he is making a regulative statement about the categorization of Christian language that structures the act of signification itself. He is saying in effect: let x (hypostasis language) be distinguished from y (ousia language, such as the attributes) such that x and y constitute two distinct sets of words. But the same statement cannot be understood as directly and immediately referring to the divine being, in which case Gregory would be saying that the hypostaseis of Father, Son, and Spirit in reality do not contain the attributes they have in common—which, of course, is nonsensical. Rather, in reality, the exact opposite is true: everything that is common to the hypostaseis is common precisely because it is “included” in the reality of each hypostasis, albeit distinctly inflected in each case. (Retrieving Nicaea, pp. 220-221)
This is not an easy paragraph and deserves a couple of re-readings. Anatolios makes a crucial point. If our question is, Does the trinitarian doctrine accurately summarize the divinely revealed propositions of Scripture? then we will always be left wondering how well the Nicene Fathers accomplished their exegetical task and why they felt it necessary to introduce technical vocabulary and confusing dialectics. Gregory of course believed that his exposition of the Trinity was firmly grounded in Scripture; but he did not pretend to approach Scripture from an objective, neutral position, as if any reader could glean the doctrine of the Trinity from the pages of the Bible.
When we grow up as children, we learn the language of our parents, siblings, and playmates, not by being drilled in grammatical rules, but just by learning the language. If we misspeak, someone corrects us and instructs us how to speak correctly. Thus the language, with its syntactical and grammatical rules, become internalized in our consciousness. Much later on, a teacher will make explicit for us the rules that we have already internalized.
This, I suggest, is something what was going on with the trinitarian crisis of the fourth century. The Church was divided by conflicting understandings and linguistic practices within the community of faith. Some, most famously Arius, started speaking about God in a manner deemed ungrammatical. Ultimately the crisis was brought to resolution not by superior exegesis and brilliant philosophical gymnastics, but by the fresh articulation of the dogmatic rules of speech that the Church had long before internalized. When the Cappadocians made explicit the ousia/hypostasis rule, the Church ultimately recognized it as a linguistic directive that she already knew and had always observed.