Exodus 3:5-6

"And he said, Draw not nigh hither: put off thy shoes from off thy feet, for the place whereon thou standest is holy ground. Moreover he said, I am the God of thy father, the God of Abraham, the God of Isaac, and the God of Jacob. And Moses hid his face; for he was afraid to look upon God" - Exodus 3:5-6 KJV