2 Chronicles 20:19-22

19And the Levites from the Kohathites and Korahites stood up to praise the LORD, the God of Israel, shouting in a very loud voice.

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.