Isaiah 19:17

And the land of Judah shall be a terror unto Egypt,.... Not by reason of war breaking out between them, they being in strict alliance with each other at this time; but on account of what they should hear had befallen the land of Judea, and the cities of it, by the invasion of Sennacherib's army, which had taken and laid them waste; the tidings of which being brought them a panic would seize them, fearing that they should next fall a sacrifice to them, because of their alliance with them, and nearness to them, there being only the land of the Philistines between them and Egypt; and Judea being invaded and overrun, the way was open for the Assyrian army into their country; and besides they might reflect, that if the judgments of God fell so heavy on his own people, what might they not expect? and the rather, as they had been the means of drawing them into idolatry, which had provoked the Lord to come out against them; as well as at the remembrance of the injuries they had formerly done them. Jarchi and Kimchi understand this of the fall and ruin of Sennacherib's army, at the siege of Jerusalem, the rumour of which reaching, Egypt would fill them with terror; or as fearing that the hand of the Lord, which was seen in that affair, would be next lifted up against them; which sense is not probable; the former is best. The word used for terror signifies "dancing", such as is not through joy, but fear, see Psalms 107:27:

everyone that maketh mention thereof; or calls to mind, or thinks of it, or speaks of it to others, what was done in the land of Judea by the Assyrian army:

shall be afraid in himself; that this will be their case quickly in Egypt:

because of the counsel of the Lord of hosts, which he hath determined against it; or "upon it", or "concerning it" x; meaning either Judea, which was known by the prophets he sent unto it; or Egypt, who might conclude this from what happened to a neighbouring nation.

x עליו επ' αυτην, Sept.; "supra eum", V. L.; "super eum", Pagninus, Montanus.