21 And after discussion with the people, he put in their places those who were to make melody to the Lord, praising him in holy robes, while they went at the head of the army, and saying, May the Lord be praised, for his mercy is unchanging for ever. 22 And at the first notes of song and praise the Lord sent a surprise attack against the children of Ammon and Moab and the people of Mount Seir, who had come against Judah; and they were overcome. 23 And the children of Ammon and Moab made an attack on the people of Mount Seir with a view to their complete destruction; and when they had put an end to the people of Seir, everyman's hand was turned against his neighbour for his destruction. 24 And Judah came to the watchtower of the waste land, and looking in the direction of the army, they saw only dead bodies stretched on the earth; no living man was to be seen.
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.