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 5

5:15 Then shall the man bring his wife unto the priest, and he shall bring her offering for her, the tenth part of an ephah of barley meal; he shall pour no oil upon it, nor put frankincense thereon; for it is an offering of jealousy, an offering of memorial, bringing iniquity to remembrance.