2 Chronicles 20:21-22

21When he had consulted with the people, he appointed those who sang to the Lord and those who praised Him in their holy (priestly) attire, as they went out before the army and said, “Praise and give thanks to the Lord, for His mercy and lovingkindness endure forever.”

22When they began singing and praising, the Lord set ambushes against the sons of Ammon, Moab, and Mount Seir, who had come against Judah; so they were struck down [in defeat].