Jamieson, Fausset and Brown on 1 Kings 13:24

24. a lion met him by the way, and slew him--There was a wood near Beth-el infested with lions (2Ki 2:24). This sad catastrophe was a severe but necessary judgment of God, to attest the truth of the message with which the prophet had been charged. All the circumstances of this tragic occurrence (the undevoured carcass, the untouched ass, the passengers unmolested by the lion, though standing there) were calculated to produce an irresistible impression that the hand of God was in it.