Exodus 3:1-3

One day Moses was taking care of Jethro’s flock. (Jethro was the priest of Midian and also Moses’ father-in-law.) When Moses led the flock to the west side of the desert, he came to Sinai, the mountain of God. There the angel of the LORD appeared to him in flames of fire coming out of a bush. Moses saw that the bush was on fire, but it was not burning up. So he said, “I will go closer to this strange thing. How can a bush continue burning without burning up?”