The LORD has raised up the foes of Rezin against him and joined his enemies together.
11. But the Lord will set up the adversaries of Rezin against him. The Israelites having been proud of their alliance with the king of Syria, and hoping that everything would succeed to their wish, Isaiah threatens a new change which will take away all their hope and utterly frustrate their designs, for the Assyrians afterwards took arms and waged war with the Syrians.
Here are terrible threatenings, which are directed primarily against Israel, the kingdom of the ten tribes, Ephraim and Samaria, the ruin of which is here foretold, with all the woeful confusions that were the prefaces to that ruin, all which came to pass within a few years after; but they look further, to all the enemies of the throne and kingdom of Christ the Son...
Commenting on Isaiah 9:8-21
Therefore the Lord shall set up the adversaries of Rezin against him,.... Set them up on high, as the word (a) signifies; exalt them above him, and make them superior to him, and conquerors of him, meaning the Assyrians; who, being sent for by Ahab, went up against Damascus, took it, and carried the people captive, and slew Rezin the king of Syria, the head...