cast himself down.. rare word. Only here and 2 Kings 4:34; 2 Kings 4:35. = Kneeling, and then placing forehead on the ground.
Related Commentaries of 1 Kings 18:42
1 Kings 18:42
42 So Ahab went up to eat and to drink. And Elijah went up to the top of Carmel; and he cast himself down upon the earth, and put his face between his knees,