20:20-30 Jehoshaphat exhorted his troops to firm faith in God. Faith inspires a man with true courage; nor will any thing help more to the establishing of the heart in shaking times, than a firm belief of the power, and mercy, and promise of God. In all our trust in the Lord, and our praises of him, let us especially look at his everlasting mercy to sinners through Jesus Christ. Never was an army so destroyed as that of the enemy. Thus God often makes wicked people destroy one another. And never was a victory celebrated with more solemn thanksgivings.
21. 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.