Apostate Dale Tuggy recently interviewed Lee Irons, who defended traditional Christology:
Lee is a Bible scholar, Dale is a philosopher. For the most part, Lee can argue circles around Dale when it comes to exegetical theology.
There were a couple of points at which Dale tripped him up. There's the tension between Lee's commitment to the eternal generation of the Son and his commitment to the aseity of the Son. Lee tried to finesse that as well as he could, given his prior commitment to both propositions, but the tension remains.
Finally, near the end of the program, Dale said [slight paraphrase]:
On the two natures reply, it's not clear to us [unitarians] how it really answers the objection. Take the case of knowing everything v. not knowing everything. So the traditional answer is that he knows everything as God but he doesn't know everything as man.
Yet it's not natures that know, but the man, the person that knows or not. So if you know something through your divine nature, it looks like it follows that you know it, the one with the nature, if you're somewhat ignorant insofar as you're human…it's the man, the person which is the subject of the ignorance. But if you accept that then you just have he knows everything and he doesn't know everything. That's an apparent contradiction.
It's hard to make sense of Dale's argument. Admittedly, he's speaking off the cuff. However, this is hardly the first time he's raised this objection, so he ought to have his formulation down pat.
i) Is he really that simple-minded, or is he attempting to confuse Christians? The orthodox argument is that Jesus is omniscience in one respect, but not omniscient in another respect. That's not contradictory. That's not even an apparent contradiction. It would only be contradictory to say Jesus is omniscient and not omniscient in the same respect. So the two-natures response is hardly reducible to "he knows everything and he doesn't know everything." That ignores key qualifications. Is Dale really that uncomprehending? Is he playing dumb, or is he truly that dim?
ii) The closest Dale comes to an explanation is to distinguish nature and person. But the "two-natures" phrase is shorthand. It doesn't mean Jesus has two impersonal natures.
To begin with, the divine nature is a personalized nature. The Son of God is a person. A rational agent.
Likewise, Jesus had/has a brain and a rational soul. Therefore, his human nature is personalized.
These aren't abstract natures, but individualized natures. Although nature and person are distinct, they are not dichotomous. And even though there's a sense in which person and nature are separable for humans, they are inseparable for God.
iii) Perhaps, hovering in the background of the objection, is the traditional formula that Jesus is one person with two natures. If so, then you don't have a one-to-one correspondence between person and nature. So maybe Dale is hinting at a contradiction from that angle. It's hard to say, because his objection is so sloppy.
Maybe his implicit objection is that Jesus can't be one person if he has two minds (human and divine). If person and nature pair off, then two natures entail two persons. If that's his objection, I'd say the following:
a) There's the question of what "person" means in Latin patrology, Greek patrology, and modern theology.
b) The meaning of the Incarnation can't be captured by single words like "nature" and "person". That's shorthand. That's not a substitute for a more detailed model. What "nature" and "person" mean in that context must be unpacked with definitions and explanations. You can't produce a contradiction by simply opposing one word ("nature") to another word ("person").
c) High-church Christians are committed to the theological settlement of the ecumenical councils, so they must try to operate within that framework. For better or worse, they are saddled with the limitations of their received tradition.
But if push came to shove, many evangelicals don't think every strand in that position is equally central in the web of belief. In terms of their priorities, I think many evangelicals begin with the full humanity and full divinity of Christ. Those are nonnegotiable. If something has to give, it's not the two natures but the one person. Not what's related, but how it's related.
d) Jesus won't be "one person" in the same sense that a merely human individual is "one person". We might say Jesus is a "complex person".
In the nature of the case, this is a unique situation, without parallel among merely human individuals.
e) However, that's not special pleading. For instance, what do dogs dream about? I don't know. I'm not a dog. A canine mind is different from a human mind, and since I can't experience both, I have no direct basis of comparison. Just as I don't know what it's like to be God Incarnate, I don't know what it's like to be a dog. Human psychology is the only frame of reference.