Numbers 8:10

8:10 Then you are to bring the Levites before the Lord, and the Israelites are to lay their hands on the Levites; ¹ 

Numbers 8:12

8:12 When ²  the Levites lay their hands on the heads of the bulls, offer ³  the one for a purification offering and the other for a whole burnt offering to the Lord, ⁴  to make atonement for the Levites.

[8:10]  ¹ sn The consecration ceremony was to be done in full view of the assembled people. In all probability the laying on of the hands was done through representatives of the tribes, and not all the people. This ritual of the imposition of hands showed that the people were taking part in the consecration, and that the Levites represented them in the service of the Lord.

[8:12]  ² tn The clause begins with a vav (ו) on the noun “the Levites,” indicating a disjunctive clause. Here it is clearly a subordinate clause prior to the instruction for Moses, and so translated as a circumstantial clause of time.

[8:12]  ³ tn The imperative is from the verb “to do; to make,” but in the sentence it clearly means to sacrifice the animals.

[8:12]  ⁴ sn The “purification offering” cleansed the tabernacle from impurity, and the burnt offering atoned by nullifying and removing the effects of sin in the Levites.