And when he had taken counsel with the people, he appointed those who were to sing to the LORD and praise him in holy attire, as they went before the army, and say, “Give thanks to the LORD, for his steadfast love endures forever.”
We have here the foregoing prayer answered and the foregoing promise performed, in the total overthrow of the enemies' forces and the triumph (for so it was rather than a victory) of Jehoshaphat's forces over them. I. Never was army drawn out to the field of battle as Jehoshaphat's was.
Commenting on 2 Chronicles 20:20-30
And when he had consulted with the people,.... His principal officers, in what order they should march, and in what manner they should form themselves, when they met the enemy, and how they should conduct as if they were to engage: he appointed singers unto the Lord; to sing his praise, and give him glory, as if the victory was already completed, it being so...
he appointed singers . . . that they should praise . . . as they went out before the army--Having arranged the line of procession, he gave the signal to move forwards. The Levites led the van with their musical instruments; and singing the 136th Psalm, the people went on, not as an army marching against an enemy, but returning in joyful triumph after a victory.