21 When he had taken counsel with the people, he appointed those who were to sing to the Lord and praise him in holy splendor, as they went before the army, saying, "Give thanks to the Lord, for his steadfast love endures forever." 22 As they began to sing and praise, the Lord set an ambush against the Ammonites, Moab, and Mount Seir, who had come against Judah, so that they were routed. 23 For the Ammonites and Moab attacked the inhabitants of Mount Seir, destroying them utterly; and when they had made an end of the inhabitants of Seir, they all helped to destroy one another. 24 When Judah came to the watchtower of the wilderness, they looked toward the multitude; they were corpses lying on the ground; no one had escaped.
Matthew Henry's Commentary on 2 Chronicles 20:21-24
Commentary on 2 Chronicles 20:20-30
(Read 2 Chronicles 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.