Albert Barnes Commentary 1 Kings 19:9

"And he came thither unto a cave, and lodged there; and, behold, the word of Jehovah came to him, and he said unto him, What doest thou here, Elijah?" — 1 Kings 19:9 (ASV)

A cave — Rather, “the cave.” Some well-known cave must be intended—perhaps the cliff of the rock (Exodus 33:22). The traditional “cave of Elijah,” which is shown in the secluded plain immediately below the highest summit of the Jebel Mousa, cannot, from its small size, be the real cavern.