Isaiah 10:11

Shall I not, as I have done unto Samaria and her idols, so do to Jerusalem and her idols?

The words are the boast of the armies of Assyria as, triumphant over Samaria in Israel, they turn their forces against Judah, claiming they will do to Jerusalem and her idols as they did to Samaria and her idols. The boast came fresh from the conquest of the greatest nations of the earth. In it Assyria claimed that its hand had found the kingdoms of the idols, whose graven images excelled those of Jerusalem and of Samaria.

Though this threat was directed at Judah, Judah had nothing to fear because its trust was in Jehovah. Hezekiah exercised faith in making ready for the coming storm and in staying his soul upon God. That faith inspired faith, so that the people rested themselves upon his words.