Thematic Bible: Natural rocks sometimes used as

And Gideon went in and made ready a kid and unleavened cakes of an ephah of flour. He put the flesh in a basket, and he put the broth in a pot, and brought it out to Him to the oak, and offered it. And the Angel of God said to him, Take the flesh and the unleavened cakes and lay on this rock, and pour out the broth. And he did so. Then the Angel of Jehovah put forth the end of the staff that was in His hand and touched the flesh and the unleavened cakes. And there rose up fire out of the rock and burned up the flesh and the unleavened cakes. Then the Angel of Jehovah went away out of his sight.

And Manoah took a kid with a food offering, and offered it upon a rock to Jehovah, and did wonderfully. And Manoah and his wife looked on. For it happened when the flame went up toward heaven from off the altar, the Angel of Jehovah went up in the flame of the altar. And Manoah and his wife looked on it and fell on their faces to the ground.