Numbers 8:11-15

11Aaron must give the Levites to the Lord as a special offering from the Israelites. Then they will be ready to do the Lord's work.

12Then the Levites must put their hands on the heads of the bulls. Then offer one bull for a sin offering and the other one for a burnt offering to the Lord. That will make peace with the Lord for the Levites sin.

13And you must cause the Levites to stand in front of Aaron and his sons. So they will be a special gift to the Lord.

14That is how you will make the Levites separate from the other Israelites. And then the Levites will be mine.

15Then after that the Levites can go in to work in the Tent of Meeting. But you must make them clean and you must bring them to me as a special gift.