John Gill Commentary 2 Kings 16:8

"And Ahaz took the silver and gold that was found in the house of Jehovah, and in the treasures of the king`s house, and sent it for a present to the king of Assyria." — 2 Kings 16:8 (ASV)

And Ahaz took the silver and gold that was found in the house
of the Lord
Which Uzziah and Jotham had put there; for all that was found there in the times of Amaziah was taken away by Jehoash king of Israel, (2 Kings 14:14)

and in the treasures of the king's house ;
whatever gold and silver he had of his own:

and sent it for a present to the king of Assyria ;
to obtain his help and assistance.