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.

And the king of Israel said to Josaphat: Take armour, and go into the battle, and put on thy own garments. But the king of Israel changed his dress, and went into the battle.

And the king of Israel saith unto Jehoshaphat to disguise himself, and to go into battle, 'And thou, put on thy garments.' And the king of Israel disguiseth himself, and goeth into battle.

And the king of Israel said to Jehoshaphat, I will make a change in my clothing, so that I do not seem to be the king, and will go into the fight; but do you put on your robes. So the king of Israel made a change in his dress and went into the fight.

Then the king of Israel said to Jehoshaphat: "Take up your armor, and enter the battle. And be clothed in your own garments." But the king of Israel changed his clothing, and he entered the war.

I will disguise myself - Ahab had probably heard of Ben-hadad's order to his captains 1-Kings 22:31.

I will disguise myself - Probably he had heard of the orders given by Ben-hadad to his thirty-two captains, to fight with the king of Israel only; that is, to make their most powerful attack where he commanded, in order to take him prisoner, that he might lead him captive whose captive he formerly was; and therefore he disguised himself that he might not be known.
But put thou on thy robes - What is meant by this? He could not mean, "Appear as the king of Judah, for they will not molest thee, as the matter of contention lies between them and me;" this is Jarchi's turn. For if Jehoshaphat aided Ahab, is it to be supposed that the Syrians would spare him in battle? A general in the civil wars of England, when he had brought his army in sight of their foes, thus addressed them: "Yonder are your enemies; if you do not kill them, they will kill you." So it might be said in the case of Jehoshaphat and the Syrians.
The Septuagint gives the clause a different and more intelligible turn: "I will cover (conceal) myself, and enter into the battle; και συ ενδυσαι τον ἱματισμον μου, but put thou on My robes." And does it not appear that he did put on Ahab's robes? And was it not this that caused the Syrians to mistake him for the king of Israel? 1-Kings 22:32.

And the king of Israel said unto Jehoshaphat, I will disguise myself, and enter into the battle,.... Change his clothes, his royal robes, and put on others, perhaps the habit of a common soldier; having, it may be, been informed by some deserters or spies, of the design of Benhadad against him. Abarbinel thinks the meaning is, that he would clothe himself with a coat of mail, and take to him the each of the instruments of war, and so go into the battle secure; this seems probable from 1-Kings 22:34 and this he might do to elude the prophecy of Micaiah:
but put thou on thy robes; his royal robes, or rather keep them on, that he might appear to be the chief commander of the army. There seems to be a good deal of insincerity and treachery in this conduct of Ahab's, whatever honour he might pretend to Jehoshaphat, or safety he might promise him in such a situation; his view seems to be to save himself at the hazard of the life of Jehoshaphat, especially if the Septuagint version could be established, "and put on my clothes"; which is natural enough, but would have been too barefaced:
and the king of Israel disguised himself, and went into the battle; as if he had been a common soldier.