As soon as the captains of the chariots saw Jehoshaphat, they said, “It is the king of Israel.” So they turned to fight against him. And Jehoshaphat cried out, and the LORD helped him; God drew them away from him.
We have here, 1. Good Jehoshaphat exposing himself in his robes, thereby endangered, and yet delivered. We have reason to think that Ahab, while he pretended friendship, really aimed at Jehoshaphat's life, to take him off, that he might have the management of his successor, who was his son-in-law, else he would never have advised him to enter into the battle with his robes on...
Commenting on 2 Chronicles 18:28-34
And it came to pass, when the captains of the chariots saw Jehoshaphat, that they said, It [is] the king of Israel. Therefore they compassed about him to fight: but Jehoshaphat cried out, and the LORD helped him; and God moved them [to depart] from him.
But Jehoshaphat cried out - "Jehoshaphat cried, and the Word of the Lord brought him assistance." - Targum.