Numbers 3:12 first declared that Levites replace the firstborn—here in 3:45 the same command is repeated for implementation.

Numbers 3:41 contains the same substitution command, now repeated to Moses in 3:45 for execution.

Numbers 3:40 commanded the census of firstborn males, which provides the count that the substitution in 3:45 will address.

Numbers 8:14 echoes the same declaration that the Levites belong to God, directly paralleling the end of 3:45.

Numbers 8:16 explicitly states that the Levites are given to God instead of the firstborn, providing the rationale for the command in 3:45.

Numbers 8:10 describes the laying on of hands ceremony that formally consecrates the Levites as substitutes for the firstborn.

Numbers 18:6 restates that the Levites are given to serve the tabernacle, expanding on their role following the substitution in 3:45.

Exodus 34:20 commands redeeming firstborn sons, which the Levite substitution in Numbers 3:45 fulfills on a national level.