Numbers 3:41-45

41You are to take the Levites for me — I am the Lord  — in place of every firstborn among the Israelites, and the Levites’ cattle in place of every firstborn among the Israelites’ cattle.”

42So Moses registered every firstborn among the Israelites, as the Lord commanded him.

43The total number of the firstborn males one month old or more listed by name was 22,273.

44The Lord spoke to Moses again:

45“Take the Levites in place of every firstborn among the Israelites, and the Levites’ cattle in place of their cattle. The Levites belong to me; I am the Lord.