Numbers 4:19

4:19 but in order that they will live and not die when they approach the most holy things, do this for them: Aaron and his sons will go in and appoint each man to his service and his responsibility.

Numbers 8:20

8:20 So Moses and Aaron and the entire community of the Israelites did this with the Levites. According to all that the Lord commanded Moses concerning the Levites, this is what the Israelites did with them.

Numbers 8:22

8:22 After this, the Levites went in to do their work in the tent of meeting before Aaron and before his sons. As the Lord had commanded Moses concerning the Levites, so they did.

Numbers 9:5

9:5 And they observed the Passover on the fourteenth day of the first month at twilight in the wilderness of Sinai; in accordance with all that the Lord had commanded Moses, so the Israelites did.