Numbers 3:40-45

40The Lord said to Moses, “Register every firstborn male of the Israelites who is at least one month old, and make a list of their names.

41I am the Lord. Take the Levites for me to be substitutes for all firstborn Israelites. Also take the animals of the Levites to be substitutes for all firstborn animals of the Israelites.”

42So Moses registered all the firstborn Israelites as the Lord commanded him.

43The total of all the firstborn males at least one month old was 22,273. They were listed by name.

44The Lord said to Moses,

45“Take the Levites to be substitutes for all the firstborn Israelites and the animals of the Levites to be substitutes for their animals. The Levites will be mine. I am the Lord.