1 Kings 22:30

22:30 The king of Israel said to Jehoshaphat, I will disguise myself, and go into the battle; but put you on your robes. The king of Israel disguised himself, and went into the battle.
-World English Bible

Other Translation

22:30 And the king of Israel said unto Jehoshaphat, I will disguise myself, and enter into the battle; but put thou on thy robes. And the king of Israel disguised himself, and went into the battle.
-King James Version