19 Then the Levites from the clans of Kohath and Korah stood to praise the Lord, the God of Israel, with a very loud shout.

20 Early the next morning the army of Judah went out into the wilderness of Tekoa. On the way Jehoshaphat stopped and said, "Listen to me, all you people of Judah and Jerusalem! Believe in the Lord your God, and you will be able to stand firm. Believe in his prophets, and you will succeed." 21 After consulting the people, the king appointed singers to walk ahead of the army, singing to the Lord and praising him for his holy splendor. This is what they sang: "Give thanks to the Lord ; his faithful love endures forever!" 22 At the very moment they began to sing and give praise, the Lord caused the armies of Ammon, Moab, and Mount Seir to start fighting among themselves.

Matthew Henry's Commentary on 2 Chronicles 20:19-22

Commentary on 2 Chronicles 20:14-19

(Read 2 Chronicles 20:14-19)

The Spirit of prophecy came upon a Levite in the midst of the congregation. The Spirit, like the wind, blows where and on whom He listeth. He encouraged them to trust in God. Let the Christian soldier go out against his spiritual enemies, and the God of peace will make him more than a conqueror. Our trials will prove our gain. The advantage will be all our own, but the whole glory must be given to God.

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.