And Jacob was left alone; and there wrestled a man with him until the breaking of the day. And there wrestled a man with him - This was doubtless the Lord Jesus Christ, who, among the patriarchs, assumed that human form, which in the fullness of time he really took of a woman, and in which he dwelt thirty-three years among men. He is here styled an angel, because he was μεγαλης βουλης Αγγελος, (see the Septuagint, Isaiah 9:7), the Messenger of the great counsel or design to redeem fallen man from death, and bring him to eternal glory; see Genesis 16:7.
But it may be asked, Had he here a real human body, or only its form? The latter, doubtless. How then could he wrestle with Jacob? It need not be supposed that this angel must have assumed a human body, or something analogous to it, in order to render himself tangible by Jacob; for as the soul operates on the body by the order of God, so could an angel operate on the body of Jacob during a whole night, and produce in his imagination, by the effect of his power, every requisite idea of corporeity, and in his nerves every sensation of substance, and yet no substantiality be in the case.
If angels, in appearing to men, borrow human bodies, as is thought, how can it be supposed that with such gross substances they can disappear in a moment? Certainly they do not take these bodies into the invisible world with them, and the established laws of matter and motion require a gradual disappearing, however swiftly it may be effected. But this is not allowed to be the case, and yet they are reported to vanish instantaneously. Then they must render themselves invisible by a cloud, and this must be of a very dense nature in order to hide a human body. But this very expedient would make their departure still more evident, as the cloud must be more dense and apparent than the body in order to hide it. This does not remove the difficulty. But if they assume a quantity of air or vapor so condensed as to become visible, and modified into the appearance of a human body, they can in a moment dilate and rarefy it, and so disappear; for when the vehicle is rarefied beyond the power of natural vision, as their own substance is invisible they can instantly vanish.
From Hosea 12:4, we may learn that the wrestling of Jacob, mentioned in this place, was not merely a corporeal exercise, but also a spiritual one; He wept and made supplication unto him. See Clarke on Hosea 12:4 (note).