John Gill's Exposition of the Whole Bible
Isaiah 36:14
Thus saith the king,.... The king of Assyria, whom he personated, whose general and ambassador he was; so he spake to command the greater awe of the people, and the more to terrify them:
let not Hezekiah deceive you; with fair words, promising protection and safety, making preparations for the defence of the city, and to oblige the besiegers to break up the siege of it:
for he shall not be able to deliver you; but if he was not, his God, whom he served, and in whom he trusted, was able to deliver them, and did deliver them; though he endeavoured to dissuade them from trusting in him, or hearkening to Hezekiah's persuasions thereunto, as in the following verse.