Numbers is a continuation of Exodus, recording the stay of the Israelites in the wilderness of Sinai until their arrival in Moab. The title of the book is derived from the two numberings of the people recorded here.

Numbers 15

15:25 And the priest shall make an atonement for all the congregation of the children of Israel, and it shall be forgiven them; for it is ignorance: and they shall bring their offering, a sacrifice made by fire unto the LORD, and their sin offering before the LORD, for their ignorance: