Albert Barnes Commentary Isaiah 36:7

"But if thou say unto me, We trust in Jehovah our God: is not that he, whose high places and whose altars Hezekiah hath taken away, and hath said to Judah and to Jerusalem, Ye shall worship before this altar?" — Isaiah 36:7 (ASV)

But if thou say to me—If you make this plea, that you believe Yahweh will protect you in your revolt. The word ‘thou’ here refers to Hezekiah, or to the ambassadors speaking in his name. In 2 Kings 18:22, it is, ‘but if ye say unto me;’ that is, you ambassadors. The sense is substantially the same.

Is it not he...—This is given as a reason why they should not put their confidence in Yahweh. The reason is, he supposed that Hezekiah had removed all the altars of Yahweh from all parts of the land, and that they could not calculate on the protection of a God whose worship had been abolished.

It is probable that Sennacherib and Rabshakeh had heard of the reformation Hezekiah had effected: of his destroying the groves and altars consecrated to idolatry in his father’s reign, and perhaps of the fact that he had even destroyed the brass serpent Moses had made, which had become an object of idolatrous worship (2 Kings 18:4). He may have supposed that all these altars and groves had been devoted to Yahweh and were connected with His worship.

He did not seem to understand that all Hezekiah had done was only to establish the worship of Yahweh in the land.

High places—The worship of idols was usually performed in groves on high places, or on the tops of hills and mountains. It seems to have been supposed that worship in such places was more acceptable to the Deity.

Perhaps this was because they thus seemed nearer the residence of the gods, or perhaps because there is a sublimity and solemnity in such places—a stillness and elevation above the world that seems favorable to devotion (see 1 Samuel 9:12; 1 Kings 3:4; 2 Kings 12:2; 2 Chronicles 33:19).

Chapels, temples, and altars were erected on such places (1 Kings 13:22; 2 Kings 17:29), and ministers and priests attended there to officiate (1 Kings 12:32; 2 Kings 17:32).

Even the kings of Judah, notwithstanding the express prohibition of Moses (Deuteronomy 12:0), were engaged in such acts of worship (2 Kings 12:4; 2 Kings 14:4; 2 Kings 15:4, 35; 2 Chronicles 15:17; 2 Chronicles 20:33); and Solomon himself sacrificed in chapels of this kind (1 Kings 3:2).

These places Hezekiah had destroyed; that is, he had cut down the consecrated groves and had destroyed the chapels and temples that had been erected there.

The fact that Ahaz, Hezekiah’s father, had been distinguished for worshipping in such places had probably led the king of Assyria to suppose that this was the proper worship of the God of the Jews. Now that Hezekiah had destroyed them all, Sennacherib seems to have inferred that Hezekiah was guilty of gross irreligion and could no longer depend on Yahweh’s protection.

And said to Judah and Jerusalem—He had commanded them to worship only in Jerusalem, at the temple. This was in strict accordance with the law of Moses, but this seems to have been understood by Sennacherib as in fact almost or completely banishing the worship of Yahweh from the land. Probably this was said to alienate the minds of the people from Hezekiah, by showing them that he had taken away their rights and privileges of worshipping God where they chose.