Jimmy Stephens stated:

On the one hand, some Trinitarians envision God’s will as unitary. God has a singular will that belongs to and “activates” through or “terminates in” the Persons. They then say the Son has two wills, one belonging to each of His natures; a divine will, a human will.

This has the odd (from a modern perspective) result that will’s correspond to nature’s not “persons.” And in talking to some of its defenders, they will even decry the use of “person” of the Trinitarian Persons as if that were biting bullets. The strength of this view or what makes it persuasive is that it avoids certain heresies revolving around the Son not being really human or whatever.

On the other hand, some Trinitarians think of will’s as belonging to persons and of the Trinitarian Members as corresponding to human persons, and so God must have three wills united by a quite distinct concept of nature. This view is probably the more popular among modern evangelical Christianity.

This social trinitarianism has the odd effect that, if we retain the historic affirmation of two-wills, Christ is two persons. So you have to do some historic revision, redaction, or whatever (as far as I can tell) to make this view work. I do think it works at least as good as the unitary-will view when you reject the two-wills views.

From my perspective, the proponents are inadvertently committing the error they accuse the other of committing. The unitary-will perspective explains one will as terminating in different outlets (hypostases or persons), and then barks at social trinitarians for doing the same (principle) thing in the Incarnation instead of the Godhead.

Meanwhile, both parties have to play around with history because Christians have never been in total agreement and the whole waving confessions strategy is one for Pharisees.

To clarify my take a little further, I think the views are just an example of a dialectic caught on from unbelieving categories. The church fathers largely depending on (crappy) Greek categories to try and construct their Trinitarian theologies. The most consistent example of this I can find is Eastern Orthodox Trinitarianism, which although I think non-heretical, is virtually indistinguishable from Neoplatonism. Just replace the One with the Father, the lower chains of being with the Son and Spirit, and add a whole lot of terminological gerrymandering to Christianize Greek intellectualization of nature and ethics.

Latin Trinitarianism is worse, if anything. It’s inconsistent, relies heavily on Aquinas and his peers, and so is just an entire tradition bending over for Aristotle to inculcate from the rear. Philosophically, Latin Trinitarianism just devolves into Aristotle’s vacuous self-thought with its divine simplicity nonsense, and you’d be better off a Muslim. Thank God Christianity is not a philosophy and neither does salvation depend on having a great philosophical schema for God’s personhood.

The best positions I’ve seen try to reframe the conversation entirely by subjecting history and philosophy to some level of Biblical theology. At least in this, Neoclassicalists and open theists are the better people.

Speaking for myself, I think God is entirely concrete in that sense. There is nothing abstract about Him. In other words, although He is uncaused, there is nothing in or about Him unable to cause something.

Even though Scholastics standardly defined these terms in something like the way you did, I don’t know that that’s a helpful distinction with respect to the words “nature” and “person,” as they are often used in Trinitarian conversations with Muslims.

I would speak more generally that the “nature” of God is just the unity or Deity of God. It’s just that which the Trinitarian Members possess together, share.

Ex. God is omnipotent. God does not instantiate an abstract universal thrice. God does not possess a single property in three essences (where there is the Divine Essence and Person Essences; this is fundamentally what I think the Scholastic strategy tries to do). God is not a collection of or emergence from abstract particulars (read: tropes).

There is numerically one reality, omnipotence, and it is possessed by the three Members. How they can possess it is so mysterious as to be virtually unspeakable. That they possess it is testified by infallible epistemic sources, and so sound doctrine even if no further explanatory principle is available.

I think that’s more safely equated to the unity of essential properties, the right ones that delineate humans from non-humans.

I think there’s a creational correspondence between God’s unity and humanity’s unity (nature), but I don’t think it’s a one-to-one overlap, and I think my view better holds to this metaphysical “analogy” than Thomism or Christian Platonism, etc.

Bosserman does a great job pointing out how, just as the Members of the Godhead share a covenant union in their being, so that they are intrinsically capable and right to speak for God, each one, so also humanity has a vestige or reflection of this trait when God designs us to have federal representatives in covenant with God.

That is, the Son can represent God to humanity because the Son possess covenanthood with the Father and Spirit just by being God. A special human can represent all humans because humans are by nature covenantally divided before God to reflect what God can do for us.