1 Kings 22:16
And the king said unto him, How many times shall I adjure thee that thou tell me nothing but that which is true in the name of the LORD? And the king said unto him, How many times shall I adjure thee that thou tell me nothing but that which is true in the name of the LORD?
Ahab hated Micaiah because the prophet spoke evil against him, his messages being unfavorable and condemning to the king. Yet in this verse Ahab solemnly adjures him to tell nothing but what is true in the name of the Lord. He made that demand because he and Jehoshaphat suspected that Micaiah's first favorable answer was not right.
What followed when the truth was told was a vision of Israel scattered without a leader, like sheep without a shepherd, with the word that the people should return each to his house in peace. That word was light and truth showing that heaven did not favor their project against Syria at Ramoth-gilead, warning that the campaign would not end in victory. Neither king heeded the warning, and both went on to battle together.
They rejected it because they had already marked out their course and were determined to follow their own judgment, making the warning unacceptable to them. Ahab was determined to proceed, while Jehoshaphat was reluctant to withdraw after pledging himself to join him. The refusal cost Ahab his life and brought the scattering of the armies of Israel and the return of the army, fulfilling the prophecy. Ahab's life might have been saved if he had accepted the message, but he refused it and perished.