Is actus purus believed in by the Orthodox?

We’d like to describe what we feel are the main objections to the two defining claims of two contrary theistic worldviews we’ve introduced, “classical” theism’s defining and non-negotiable claim that God is actus purus (a God in whom there is no unfulfilled potential) and Process theism’s belief in a God who is, if we may coin the phrase, processu operis, a “work in process” (whose existence and perfections are constituted in and as the ever changing process of God’s ongoing relationship with the universe).

Before we jump into the objections of these two understandings of God, I want first to clarify our earlier question about whether the Orthodox affirm actus purus. It is after all a well-known axiom of scholastic (Western) theology embodied in Aquinas, and the Orthodox are on record as criticizing scholasticism in general and the failure of the West to make a key Orthodox distinction between God’s essence and his energies. Fr Aidan also earlier registered some reservation about our suggestion that the Orthodox believe in actus purus. So before we describe the objections to both ‘classical’ and ‘process’ views, we’d like to offer a clarification.

All we mean by actus purus is what we understand Orthodox theologian David Hart to refer to as the denial of all potentiality in God. If that’s not an Orthodox belief, that would be great news to us. Besides Hart, I also remember discussing this over lunch with Paul Gavrilyuk a couple of years ago. He had mentioned what a promising work he thought Richard Creel’s Divine Impassibility (1986) was. “But Creel is an open theist,” I thought to myself. So when I asked Paul about open theism and what the main Orthodox objection(s) to it would be, he slightly shook his head and said that it goes too far by placing God “in time,” and that this wasn’t compatible with Orthodoxy. I get this sort of reminder that the Orthodox do share the fundamental tenet of actus purus (viz., that there is no potentiality in God) even though they don’t use the phrase and can criticize what the West does with it. But we’re open to the Orthodox clarifying this for us.