Numbers 4:19

4:19 but in order that they will live and not die when they approach the most holy things, do this for them: Aaron and his sons will go in and appoint each man to his service and his responsibility.

Numbers 6:9

Contingencies for Defilement

6:9 “‘If anyone dies very suddenly beside him and he defiles his consecrated head, then he must shave his head on the day of his purification – on the seventh day he must shave it.

Numbers 16:17

16:17 And each of you take his censer, put incense in it, and then each of you present his censer before the Lord: 250 censers, along with you, and Aaron – each of you with his censer.”