2 Chronicles 20:1-4, 21-26

It came to pass after this also, that the children of Moab, and the children of Ammon, and with them other beside the Ammonites, came against Jehoshaphat to battle. Then there came some that told Jehoshaphat, saying, There cometh a great multitude against thee from beyond the sea on this side Syria; and, behold, they be in Hazazon-tamar, which is Engedi. And Jehoshaphat feared, and set himself to seek the LORD, and proclaimed a fast throughout all Judah. And Judah gathered themselves together, to ask help of the LORD: even out of all the cities of Judah they came to seek the LORD.

And when he had consulted with the people, he appointed singers unto the LORD, and that should praise the beauty of holiness, as they went out before the army, and to say, Praise the LORD; for his mercy endureth for ever. And when they began to sing and to praise, the LORD set ambushments against the children of Ammon, Moab, and mount Seir, which were come against Judah; and they were smitten. For the children of Ammon and Moab stood up against the inhabitants of mount Seir, utterly to slay and destroy them: and when they had made an end of the inhabitants of Seir, every one helped to destroy another. And when Judah came toward the watch tower in the wilderness, they looked unto the multitude, and, behold, they were dead bodies fallen to the earth, and none escaped. And when Jehoshaphat and his people came to take away the spoil of them, they found among them in abundance both riches with the dead bodies, and precious jewels, which they stripped off for themselves, more than they could carry away: and they were three days in gathering of the spoil, it was so much. And on the fourth day they assembled themselves in the valley of Berachah; for there they blessed the LORD: therefore the name of the same place was called, The valley of Berachah, unto this day.