2 Kings 18:19
And Rab-shakeh said unto them, Speak ye now to Hezekiah, Thus saith the great king, the king of Assyria, What confidence is this wherein thou trustest? And Rab-shakeh said unto them, Speak ye now to Hezekiah, Thus saith the great king, the king of Assyria, What confidence is this wherein thou trustest?
Because Israel and Judah had grown weak and apostate, God's name was no longer feared among the nations but had become a subject of continual blasphemy. In that condition Assyria pressed its demand that Judah surrender, and Rabshakeh confronted Hezekiah with a demand to state the basis of his confidence in resisting.
The challenge called into question both Hezekiah's own military strength and his trust in the Lord. Its words were a blasphemous taunt and reviling against God. They were spoken loudly in the Jewish language so that the people on Jerusalem's wall could hear them.