9 And it came to pass in the fourth year of king Hezekiah, which was the seventh year of Hoshea the son of Elah, king of Israel, [that] Shalmaneser king of Assyria came up against Samaria and besieged it. 10 And at the end of three years they took it; in the sixth year of Hezekiah, that is, the ninth year of Hoshea king of Israel, Samaria was taken.
Matthew Henry's Commentary on 2 Kings 18:9-10
Commentary on 2 Kings 18:9-16
(Read 2 Kings 18:9-16)
The descent Sennacherib made upon Judah, was a great calamity to that kingdom, by which God would try the faith of Hezekiah, and chastise the people. The secret dislike, the hypocrisy, and lukewarmness of numbers, require correction; such trials purify the faith and hope of the upright, and bring them to simple dependence on God.