Numbers 18:13
18:13 And whatever first ripe fruit in their land they bring to the Lord will be yours; everyone who is ceremonially clean in your household may eat of it.
Numbers 19:8
19:8 The one who burns it 1 must wash his clothes in water and bathe himself in water. He will be ceremonially unclean until evening.
Numbers 31:24
31:24 You must wash your clothes on the seventh day, and you will be ceremonially clean, and afterward you may enter the camp.’”
1 sn Here the text makes clear that he had at least one assistant.