Isaiah 36

As the officials from the king of Assyria taunted the people of Jerusalem they made one truthful statement. "Hezekiah can't save you."
We don't have a record, in this passage, of what Hezekiah said to the people, but we can be confident that it was not a proclamation of his own abilities to rescue Jerusalem from the Assyrian army. Hezekiah knew that only the God of Israel welded such power. That is where Hezekiah placed his faith.
Stuart