Albert Barnes Commentary Isaiah 36:18

"Beware lest Hezekiah persuade you, saying, Jehovah will deliver us. Hath any of the gods of the nations delivered his land out of the hand of the king of Assyria?" — Isaiah 36:18 (ASV)

Has any of the gods of the nations ... - This is said to show them the impossibility, as he supposed, of being delivered from the arm of the king of Assyria. He had conquered all before him, and not even the gods of the nations had been able to rescue the lands where they were worshipped from the hands of the victorious invader. He inferred, therefore, that Yahweh, the God of Palestine, could not save their land.