2 Chronicles 20:21
And when he had consulted with the people, he appointed singers unto the Lord, and that should praise the beauty of holiness, as they went out before the army, and to say, Praise the Lord; for his mercy endureth for ever. (2 Chronicles 20:21)
Before the army.
As the armies of Judah advanced against the enemy the singers constituted the vanguard, shouting, not a cry of battle, but praises to God.