Numbers 3:38
3:38 But those who were to camp in front of the tabernacle on the east, in front of the tent of meeting, were Moses, Aaron, and his sons. They were responsible for the needs of the sanctuary and for the needs of the Israelites, but the unauthorized person who approached was to be put to death.
Numbers 9:13
9:13 But the man who is ceremonially clean, and was not on a journey, and fails to keep the Passover, that person must be cut off from his people. Because he did not bring the Lord’s offering at its appointed time, that man must bear his sin.
Numbers 18:7
18:7 But you and your sons with you are responsible for your priestly duties, for everything at the altar and within the curtain. And you must serve. I give you the priesthood as a gift for service; but the unauthorized person who approaches must be put to death.”
Numbers 19:18-20
19:18 Then a ceremonially clean person must take hyssop, dip it in the water, and sprinkle it on the tent, on all its furnishings, and on the people who were there, or on the one who touched a bone, or one killed, or one who died, or a grave.
19:19 And the clean person must sprinkle the unclean on the third day and on the seventh day; and on the seventh day he must purify him, and then he must wash his clothes, and bathe in water, and he will be clean in the evening.
19:20 But the man who is unclean and does not purify himself, that person must be cut off from among the community, because he has polluted the sanctuary of the Lord; the water of purification was not sprinkled on him, so he is unclean.