And it shall be on Aaron to serve. And his sound shall be heard when he goes in to the holy place before Jehovah, and when he comes out, so that he will not die.
and Jehovah said to Moses, Speak to Aaron your brother, that he does not come at all times into the sanctuary within the veil before the mercy-seat, which is on the Ark, so that he will not die. For I will appear in the cloud on the mercy-seat.