2 Chronicles 20:20-24

20Early in the morning they got up and left for the Wilderness of Tekoa. As they set out, Jehoshaphat stood up and said, “Hear me, O people of Judah and Jerusalem. Believe in the LORD your God, and you will be upheld; believe in His prophets, and you will succeed.”

21Then Jehoshaphat consulted with the people and appointed those who would sing to the LORD and praise the splendor of His holiness. As they went out before the army, they were singing:

22The moment they began their shouts and praises, the LORD set ambushes against the men of Ammon, Moab, and Mount Seir who had come against Judah, and they were defeated. 23The Ammonites and Moabites rose up against the inhabitants of Mount Seir, devoting them to destruction.1 And when they had finished off the inhabitants of Seir, they helped to destroy one another.

24When the men of Judah came to a place overlooking the wilderness, they looked for the vast army, but there were only corpses lying on the ground; no one had escaped.