Elijah’s position in this verse was a stance for deep meditation. He was probably thinking about the victory of the Lord over the priests of the pagan god Baal (1 Kings 18:27) and praising Him for His awesome power.
In this meditative position, a person sat on the ground with his knees drawn up to his chin. Elijah also pushed his head forward until his face was literally “between his knees.”
1 KINGS 18:46 – He [Elijah] girded up his loins [tucking his cloak into his belt, NIV], and ran before Ahab to the entrance of Jezreel.