Then Isaiah the son of Amoz sent to Hezekiah, saying, “Thus says the LORD, the God of Israel: Your prayer to me about Sennacherib king of Assyria I have heard.
We have here the gracious copious answer which God gave to Hezekiah's prayer. The message which he sent him by the same hand (Kg2 19:6, Kg2 19:7), one would think, was an answer sufficient to his prayer; but, that he might have strong consolation, he was encouraged by two immutable things, in which it was impossible for God to lie, Heb 6:18.
Commenting on 2 Kings 19:20-34
HEZEKIAH'S PRAYER. (2Ki. 19:14-34) Hezekiah received the letter . . . and went up into the house of the Lord--Hezekiah, after reading it, hastened into the temple, spread it in the childlike confidence of faith before the Lord, as containing taunts deeply affecting the divine honor, and implored deliverance from this proud defier of God and man.
Commenting on 2 Kings 19:14-34
Then Isaiah . . . sent--A revelation having been made to Isaiah, the prophet announced to the king that his prayer was heard. The prophetic message consisted of three different portions:--First, Sennacherib is apostrophized (Kg2 19:21-28) in a highly poetical strain, admirably descriptive of the turgid vanity, haughty pretensions, and presumptuous impiety of the Assyrian despot.