Exodus 34:29-35

It came about when Moses was coming down from Mount Sinai (and the two tablets of the testimony were in Moses’ hand as he was coming down from the mountain), that Moses did not know that the skin of his face shone because of his speaking with Him. So when Aaron and all the sons of Israel saw Moses, behold, the skin of his face shone, and they were afraid to come near him. Then Moses called to them, and Aaron and all the rulers in the congregation returned to him; and Moses spoke to them. Afterward all the sons of Israel came near, and he commanded them to do everything that the LORD had spoken to him on Mount Sinai. When Moses had finished speaking with them, he put a veil over his face. But whenever Moses went in before the LORD to speak with Him, he would take off the veil until he came out; and whenever he came out and spoke to the sons of Israel what he had been commanded, the sons of Israel would see the face of Moses, that the skin of Moses’ face shone. So Moses would replace the veil over his face until he went in to speak with Him.