Exodus 34:34-35
34:34 But when Moses went in before the Lord to speak with him, he would remove the veil until he came out. Then he would come out and tell the Israelites what he had been commanded.
34:35 When the Israelites would see the face of Moses, that the skin of Moses’ face shone, Moses would put the veil on his face again, until he went in to speak with the Lord.