2 Chronicles 20:18
And Jehoshaphat bowed his head with his face to the ground: and all Judah and the inhabitants of Jerusalem fell before the LORD, worshipping the LORD. And Jehoshaphat bowed his head with his face to the ground: and all Judah and the inhabitants of Jerusalem fell before the LORD, worshipping the LORD.
The bowing and worship took place before the battle, as the response of Jehoshaphat with all Judah and the inhabitants of Jerusalem to God's assurance and promise of deliverance. That assurance came to a terror-stricken people facing a great multitude, telling them not to be afraid nor dismayed because the battle was not theirs but God's. The word specified that they would go down against the enemy by the cliff of Ziz, would not need to fight but would set themselves, stand still, and see the salvation of the Lord with them, and would go out the next day because the Lord would be with them.
Jehoshaphat's bowing his head with his face to the ground and the people's falling before the Lord expressed humility, reverence, trust, and dependence on God. The worship acknowledged that God Himself fights the battle and brings deliverance. Immediately after this bowing in worship, the Levites stood to praise God loudly. The worship shows trust for today that God is the strength of His people and their strong tower of defense, so they are not to trust in princes or put men in the place of God and are not to look at supposed impossibilities, and in every emergency the battle belongs to Him whose resources are limitless, so apparent impossibilities make the victory greater.