Isaiah 31:8

“Then shall the Assyrian fall with the sword, not of a mighty man, &c.] That is, the Assyrian army under Sennacherib their king, which besieged Jerusalem in Hezekiah’s time; which, as soon as the people were brought to a sense of their sin, and repentance for it, and cast away their idols as a proof of it, were utterly destroyed; but not in battle, not by the sword of Hezekiah, or any of his valiant generals: and the sword, not of a mean man, shall devour him; neither the sword of a general, nor of a private soldier, nor indeed of any man, but of an angel; (see <121935>2 Kings 19:35): but he shall flee from the sword; from the drawn sword of the angel, who very probably appeared in such a…”

“Assyrian--Sennacherib, representative of some powerful head of the ungodly in the latter ages [HORSLEY]. sword, not of . . . mighty . . . mean man--but by the unseen sword of God. flee--Sennacherib alone fled homewards after his army had been destroyed (Isa 37:37). young men--the flower of his army. discomfited--rather, "shall be subject to slavery"; literally, "shall be liable to tribute," that is, personal service (Deu 20:11; Jos 9:21) [MAURER]. Or, not so well, "shall melt away" [ROSENMULLER].”

“Then shall the Assyrian fall with the sword - The sword is often used as an instrument of punishment. It is not meant here literally that the sword would be used, but it is employed to denote that complete destruction would come upon them. Not of a mighty man - The idea here is, that the army should not fall by the valor of a distinguished warrior, but that it should be done by the direct interposition of God (see Isaiah 37:36). Of a mean man - Of a man of humble rank. His army shall not be slain by the hand of mortals. But he shall flee - The Assyrian monarch escaped when his army was destroyed, and fled toward his own land; Isaiah 37:37. From the sword - Margin, ‘For fear of.’ The Hebrew…”

“The sword - Not of any man, but of an angel. Discomfited - Heb. shall melt away, a great part of them being destroyed by the angel; and the hearts of the rest melting for fear. Isaiah 31:9”

“shall the: Isa 10:16-19, Isa 10:33, Isa 10:34, Isa 14:25, Isa 29:5, Isa 30:27-33, Isa 37:35; Kg2 19:34-37; Ch2 32:21; Hos 1:7 he shall flee: Isa 37:37, Isa 37:38 from the sword: or, for fear of the sword discomfited: or, tributary. Heb. for melting, or tribute. Isaiah 31:9”

“The second motive is, that Israel will not be rescued by men, but by Jehovah alone; so that even He from whom they have now so deeply fallen will prove Himself the only true ground of confidence. "And Asshur falls by a sword not of a man, and a sword not of a man will devour him; and he flees before a sword, and his young men become tributary. And his rock, for fear will it pass away, and his princes be frightened away by the flags: the saying of Jehovah, who has His fire in Zion, and His furnace in Jerusalem." The lxx and Jerome render this falsely φεύξεται οὐκ (לא) ἀπὸ προσώπου μαχαίρας. לו is an ethical dative, and the prophet intentionally writes "before a sword" without any…”