I am as thou art. — The answer is apparently one of deference, as well as friendship, to the stronger kingdom. It must be remembered that, as the whole chapter shows, Ahab had now returned to the worship of the Lord.
Related Commentaries of 1 Kings 22:4
1 Kings 22:4
4 And he said unto Jehoshaphat, Wilt thou go with me to battle to Ramothgilead? And Jehoshaphat said to the king of Israel, I am as thou art, my people as thy people, my horses as thy horses.