Exodus 28:43

28:43 These must be on Aaron and his sons when they enter to the tent of meeting, or when they approach the altar to minister in the Holy Place, so that they bear no iniquity and die. It is to be a perpetual ordinance for him and for his descendants after him.

Exodus 33:1

33:1 The Lord said to Moses, “Go up from here, you and the people whom you brought up out of the land of Egypt, to the land I promised on oath to Abraham, to Isaac, and to Jacob, saying, ‘I will give it to your descendants.’