Here’s my summary of the Trinitarian theology of Gregory of Nyssa which I accidentally prepared for a PhD course I’m in at TEDS taught by Dr. Thomas McCall called Trinity and Atonement. I thought we had to do a summary every week but we don’t. So this was a waste, unless you read it and enjoy it. So read it and enjoy it.
On the Holy Spirit
In Gregory of Nyssa’s defense of the doctrine of the Holy Spirit against the Macedonians, he resolutely denies their accusations of entertaining lofty conceptions about the Trinity. Instead, Gregory insists that he and his cohorts have merely held to the biblical teaching of the Trinity, including the full divinity of the Holy Spirit in the Godhead, adding nothing new of their own invention.
Gregory explains his view using a torch analogy. If we see three torches all burning, then they are all fire. It doesn’t matter if the first torch was used to light the second and then the second was used to light the third, if they are all fire then they are all equally fire. Similarly, the Father, the Son, and the Spirit are all equally divine, it doesn’t matter than the Spirit is named third, or that the Son is begotten of the Father, just as each torch is equally fire, so the three persons of the Trinity are God.
Gregory defends his position with a firm disjunction, either the Spirit is on the side of Creator, and thus God, or else he is on the side of creation, and thus not God. He argues that there can be no middle ground of half created, half uncreated. And since it would be monstrous to claim that the Holy Spirit is part of Creation, we must affirm that the Holy Spirit is truly God, and if truly God then He can’t be any less than God, he can’t be diminished in anyway.
On Not Three Gods
In his essay On Not Three Gods, Gregory puts forth two major arguments against the claim that Christians are tri-theists. The first argument responds to an argument from analogy that says, if we can say that Peter, James, and John each partake in the same human nature yet we refer to them in the plural as “men” and not in the singular “man”, then why shouldn’t we be consistent when it comes to God. If God is three persons each partaking in the same divine nature, then we should say Gods instead of God just as we say men instead of man refereeing to more than one human person.
To this argument, Gregory responds that the use of the plural men is merely colloquial and not the proper usage. It shouldn’t actually be used but it’s become a habit for us to speak of men rather than man, and that habit doesn’t seem to be ending any time soon. He argues that in reference to man, it’s not a big deal whether we say man or men in reference to more than one human person because there is not as much at stake. However, when it comes to the Trinity we need to actually practice the proper usage, and thus we believe in one God, not gods.
His second argument against the charge of tri-theism draws upon God’s operational unity. Gregory argues that though there are three persons of the Trinity, the Father, Son, and Spirit act in unity in the actions of the Godhead. He gives a commonsense example from life. God has given us life, in so doing the Godhead is not split at all, we can’t say that God has given me lives, we have one life not three. So, we see from God’s actions that there is an operational unity so interweaved that it prevents any sort of plural enumeration in the Godhead. God is one God. Though the Godhead is operationally unified, deity itself is unlimited and cannot even be limited by a name like Godhead, thus there is more to God than just his unity.
This last point anticipates the charge of Unitarianism. But Gregory further argues that cause is the way to distinguish between the persons of the Trinity. The Father causes the Son who causes the Spirit. The Father is ungenerated, the Son is generated, and the Spirit suffers no loss due to the interposition of the Son between the Father and he. Thus, Christians believe in one God, evidenced by His operationally unified work in creation, yet Christians believe in a Trinitarian God whose persons can be distinguished by their cause.
The Great Catechism
In this work, Gregory warns against the twin ditches of Judaism, meaning Unitarianism, and polytheism. In striking a biblically faithful path between the two, he argues from the Divine Logos of God. He says that although our human logos is limited, the divine Logos cannot be, it is indestructible. It is also living since the rational cannot be lifeless, stones are not rational. He then argues that the Logos must have its own life and not merely participation in another or it would lose its simplicity. But, since it has its own life, it must also have a will, and a good one at that since it is Divine.
Thus, through reasoning about the Divine Word or Logos, we are able to avoid both Unitarianism and polytheism since the Word has life and activity of its own, yet its existence is grounded or derived from the Father. Since this is the case, the Word has all the attributes of the Father’s nature as well. So, we have distinction in the persons of the Trinity, yet one divine nature, the Godhead.
On the Holy Trinity
In On the Holy Trinity, Gregory closely follows the thrust of his other arguments presented thus far. Once again, his detractors charge him with positing three Gods, yet he continues to resolutely anathematize those who claim there are three Gods- he says they are not even Christians. Yet, after he forcefully defends against tri-theism, his detractors turn and label him with Sabellianism.
So again, Gregory clarifies that God’s goodness, power, and the Godhead are one. Scripture affirms it in verses such as Colossians 2:9, and so Gregory follows Scripture in affirming the unity of the Godhead. Those who would deny his affirmation of unity in the Godhead are left in a precarious position. To say that the Godhead is three is to affirm three Gods, a position that Gregory says is anathema, but to deny the Godhead is out right atheism, so the only option is to affirm, with Scripture mind you, that the Godhead is one.