Numbers 8:10

⁸And they shall take one calf of the herd, and its meat offering, fine flour mingled with oil: and thou shalt take a calf of a year old of the herd for a sin offering.

⁹And thou shalt bring the Levites before the tabernacle of witness; and thou shalt assemble all the congregation of the sons of Israel.

— Numbers 8:10 —

¹¹And Aaron shall separate the Levites for a gift before the Lord from the children of Israel: and they shall be prepared to perform the works of the Lord.

¹²And the Levites shall lay their hands on the heads of the calves; and thou shalt offer one for a sin offering, and the other for a whole burnt offering to the Lord, to make atonement for them.