Exodus 3:4-6

When the LORD saw that he turned away [from the flock] to look, God called to him from the midst of the bush and said, “Moses, Moses!” And he said, “Here I am.” Then God said, “Do not come near; take your sandals off your feet [out of respect], because the place on which you are standing is holy ground.” Then He said, “I am the God of your father, the God of Abraham, the God of Isaac, and the God of Jacob.” Then Moses hid his face, because he was afraid to look at God.