He was of the prophets - Josephus and others conjecture that this prophet was Micaiah, the son of Imlah (but compare 1-Kings 20:13 note).

Took the ashes away - He took the bandage from off his eyes: see on 1-Kings 20:38 (note). It was no doubt of thin cloth, through which he could see, while it served for a sufficient disguise.

And he hasted, and took away the ashes from his face,.... Took off the linen cloth from his eyes, unveiled or unmasked himself:
and the king of Israel discerned him, that he was of the prophets; he knew him again, having seen him once or twice before; otherwise there could be nothing in his face that could discover him to be a prophet, rather he was to be known by his habit.

Then the disciple of the prophets drew the bandage quickly from his eyes, so that the king recognised him as a prophet, and announced to him the word of the Lord: "Because thou hast let go out of thy hand the man of my ban (i.e., Benhadad, who has fallen under my ban), thy life shall stand for his life, and thy people for his people," i.e., the destruction to which Benhadad was devoted will fall upon thee and thy people. The expression אישׁ־חרמי (man of my ban) showed Ahab clearly enough what ought to have been done with Benhadad. A person on whom the ban was pronounced was to be put to death (Leviticus 27:29).