Exodus 34:29-35

²⁹And 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. ³⁰So when Aaron and all the sons of Israel saw Moses, behold, the skin of his face shone, and they were afraid to approach him. ³¹Then Moses called to them, and Aaron and all the rulers in the congregation returned to him; and Moses spoke to them. ³²Afterward all the sons of Israel came near, and he commanded them to do everything that the Lord had spoken to him on Mount Sinai. ³³When Moses had finished speaking with them, he put a veil over his face. ³⁴But 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, ³⁵the sons of Israel would see the face of Moses, that the skin of Moses’ face shone. So Moses would put the veil back over his face until he went in to speak with Him.