Charles Ellicott Commentary 1 Kings 18:39

"And when all the people saw it, they fell on their faces: and they said, Jehovah, he is God; Jehovah, he is God." — 1 Kings 18:39 (ASV)

They fell on their faces. —Exactly as in Leviticus 9:24, at the inauguration of the sacrifices of the new Tabernacle by the fire from heaven, with the characteristic addition of the cry, “Jehovah; He, and He only, is God.”