What does 2 Kings 19:17 mean?

Hezekiah received the letter from the hand of the messengers and read it. Then Hezekiah went up to Yahweh’s house, and spread it before Yahweh.

Hezekiah prayed before Yahweh, and said, “Yahweh, the God of Israel, who sit above the cherubim, you are the God, even you alone, of all the kingdoms of the earth. You have made heaven and earth.

Incline your ear, Yahweh, and hear. Open your eyes, Yahweh, and see. Hear the words of Sennacherib, which he has sent to defy the living God.

and have cast their gods into the fire; for they were no gods, but the work of men’s hands, wood and stone. Therefore they have destroyed them.

Now therefore, Yahweh our God, save us, I beg you, out of his hand, that all the kingdoms of the earth may know that you, Yahweh, are God alone.”

Then Isaiah the son of Amoz sent to Hezekiah, saying, “Yahweh, the God of Israel, says ‘You have prayed to me against Sennacherib king of Assyria, and I have heard you.