The remnant shall return, even the remnant of Jacob, unto the mighty God.

Jamieson-Fausset-Brown Bible Commentary

21. mighty God-(Isa 9:6) the God who shall have evinced such might in destroying Israel's enemies. As the Assyrians in Sennacherib's reign did not carry off Judah captive, the returning "remnant" cannot mainly refer to this time.

Matthew Henry's Concise Commentary

10:20-34 By our afflictions we may learn not to make creatures our confidence. Those only can with comfort stay upon God, who return to him in truth, not in pretence and profession only. God will justly bring this wasting away on a provoking people, but will graciously set bounds to it. It is against the mind and will of God, that his people, whatever happens, should give way to fear. God's anger against his people is but for a moment; and when that is turned from us, we need not fear the fury of man. The rod with which he corrected his people, shall not only be laid aside, but thrown into the fire. To encourage God's people, the prophet puts them in mind of what God had formerly done against the enemies of his church. God's people shall be delivered from the Assyrians. Some think it looks to the deliverance of the Jews out of their captivity; and further yet, to the redemption of believers from the tyranny of sin and Satan. And this, because of the anointing; for his people Israel's sake, the believers among them that had received the unction of Divine grace. And for the sake of the Messiah, the Anointed of God. Here is, ver. 28-34, a prophetical description of Sennacherib's march towards Jerusalem, when he threatened to destroy that city. Then the Lord, in whom Hezekiah trusted, cut down his army like the hewing of a forest. Let us apply what is here written, to like matters in other ages of the church of Christ. Because of the anointing of our great Redeemer, the yoke of every antichrist must be broken from off his church: and if our souls partake of the unction of the Holy Spirit, complete and eternal deliverances will be secured to us.