2 Chronicles 18:3, 29-32

Ahab king of Israel asked Jehoshaphat king of Judah, “Will you go with me against Ramoth Gilead?” Jehoshaphat replied, “I am as you are, and my people as your people; we will join you in the war.”

The king of Israel said to Jehoshaphat, “I will enter the battle in disguise, but you wear your royal robes.” So the king of Israel disguised himself and went into battle. Now the king of Aram had ordered his chariot commanders, “Do not fight with anyone, small or great, except the king of Israel.” When the chariot commanders saw Jehoshaphat, they thought, “This is the king of Israel.” So they turned to attack him, but Jehoshaphat cried out, and the LORD helped him. God drew them away from him, for when the chariot commanders saw that he was not the king of Israel, they stopped pursuing him.