Charles Ellicott Commentary 2 Chronicles 20:18

"And Jehoshaphat bowed his head with his face to the ground; and all Judah and the inhabitants of Jerusalem fell down before Jehovah, worshipping Jehovah." — 2 Chronicles 20:18 (ASV)

Bowed his head. —The king bowed, face earthward, and the people prostrated themselves upon their faces, both to do worship to Jehovah. (Joshua 5:14; 1 Chronicles 21:16; Exodus 34:8.)