Leviticus 10:6-7

6Moses said to Aaron and to his sons, ‘Comb your hair. Do not tear your clothes. If you do that, you will die. And the Lord will be angry with all the people. But Israel's people can show that they are sad. They are sad because the Lord has killed Nadab and Abihu with fire.

7If you go away from the door of the Tent of Meeting you will die. You will die because the Lord's holy oil is on you.’ So Aaron and his sons did as Moses had said.