Some time ago, I started to read The Mystical Theology of the Eastern Church by Vladimir Lossky. I really should finish it some time, but at the time I had to stop. Early in the book, Lossky said that Augustine and Aquinas have a false vision of the Trinity that amounts to making a fourth thing, the unity, that holds the three persons of Father, Son, and Holy Spirit together. This is the sort of annoying thing that makes me put a book down for a time.
I am now in the midst of Book 1 of Peter Lombard’s Sentences, the essential textbook of medieval scholasticism (upon which Aquinas and man others wrote commentaries). Book 1 deals with the mystery of the Trinity, and it is mostly systematically arranged excerpts from St Augustine, the majority of them from Augustine’s On the Trinity.
Last week, my reading brought me through questions of essence and unity.
In the twelfth-century scholastic view represented by Lombard’s arrangement of and commenting upon St Augustine, it is asserted that each person of the Trinity possesses the fulness of the divine essence/usia (medieval Latins do not transliterate ousia). There is no essence as a fourth thing which they all share. The same divine essence, that which God is, the reality of God’s own self, is the essence of each person of the Trinity, and it is not divided. There is only one essence, of course, even with three hypostases.
But this is no different from the Greek Fathers — indeed, the Lombard enlists St John Damascus in these discussions. There are three hypostases, one ousia. We can only distinguish the three hypostases through their relations to one another (see St Gregory of Nazianzus) — or, in the Lombard’s terms, their properties (he actually uses both).
Essence, as I understand it, is something that everyone and everything has, and, like nature, it requires some sort of hypostasis or subsistence or grounded reality to manifest itself. So if there is one God, as all Trinitarian Christians proclaim, then there is one essence. If there are three persons, as all Trinitarian Christians claim, but only one essence, somehow we must say that each of them has the fulness of the divine essence in himself.
The divine unity cannot be a quartum quid or fourth thing as Lossky claims, moreover, because that would break divine simplicity, something the Greek and Latin Fathers, not to mention the Scholastics, are strong on. Divine simplicity is the idea that God is not composed of parts. As soon as you ask the question what God is made of, you realise that any composition diminishes his perfections and makes him lesser. To posit the unity of the Trinity as an actual fourth thing that the other three share shatters the simplicity.
The divine unity cannot be a quartum quid because that would break divine equality — and it is in the discussions equality in Book 1, Distinction XIX of the Sentences, that many of my initial thoughts began to arise in this direction. Each of them has to be fully God. As the chapter heading of DXIX, ch. 2.1 says, “Eternity, Greatness, and Might in God Are One Thing, Although They Are Posited As If They Were Diverse.” 2.2’s heading declares, “Greatness is the essence of God.” God is his greatness. God is his justice. God is his holiness. Now, so far this is simplicity.
Simplicity secures the equality because by saying that the Father, Son, and Holy Spirit are all one essence, then we are saying that the greatness of the Father is the same greatness as that of the Son; in God, all is essence, nothing is accident. This means that even if we were to posit “unity” as an attribute of God that is, like all truly divine attributes, common to all three persons, we would not be adding a fourth thing; that would be the same as saying God’s justice is adding a fourth thing.
Anyway, the equality of God means that the Father is not greater or more just or more holy than the Son or the Spirit, for they are all one essence. The glory of each is the glory of all.
It is also worth putting to rest the idea that perhaps lies behind this moment in Lossky, that in the West we are often mere monotheists and in the East they run the risk of becoming tritheists. This idea does not do justice to any of the traditions. Reading through the careful work of the Lombard’s Sentences shows me that the foundations of the Latin tradition, not just in Augustine but in Hilary as well, are as committed to the actual persons, or hypostases, as the Greeks such as St Gregory of Nazianzus and St John of Damascus. And my years teaching the Nicene Controversy and the Ecumenical Councils have shown that the Greeks are not social Trinitarians, let alone tritheists.
We agree on the Most Holy Trinity more than many would have us believe.