The Bible does not say who Cain’s wife was. This information is not relevant to the story. Cain probably married a sister or niece of his. Adam and Eve had other children besides Cain, Abel and Sete.
The Bible says that all people in the world are descendants of Adam and Eve ( Genesis 3:20 ). Therefore, Cain’s wife must have been his relative. To better understand where Cain’s wife came from, let’s look at the chronology of events in the Bible:
- Adam and Eve were expelled from Eden
- Adam had relations with Eve and Cain was born ( Genesis 4: 1) – other translations say that Adam “knew” Eve; in this context “knowing” means having relationships
- Eve had another child – Abel ( Genesis 4: 2)
- Cain and Abel grew up and followed different professions
- Cain and Abel offered sacrifices to God but God rejected Cain’s sacrifice
- Cain was jealous of Abel and killed him ( Genesis 4: 8)
- God confronted Cain and drove him out of his parents’ land
- Cain fled to a place called Node ( Genesis 4:16)
- Adam and Eve had other sons and daughters after Abel’s death ( Genesis 4:25; Genesis 5: 4 )
- Cain had intercourse with his wife and she had a son ( Genesis 4:17) – again here some translations use “to know” in the sense of having intercourse
Here’s why God rejected Cain’s sacrifice.
The Bible does not say how much time has passed between these events or everything that has happened in between. For example, the Bible tells of Abel’s birth shortly after Cain’s birth without saying that at least 9 months passed between the two events. The Bible does not say:
- When Cain married
- If Adam and Eve had other sons and daughters before Seven – Cain seems to imply that he had other relatives who could kill him but the Bible is unclear ( Genesis 4: 13-14)
See also: what was the mark of Cain?
Most likely, Cain married one of his sisters. If he married too late, he may have married a niece or sister who was born after Sete. At that time sibling marriage was necessary because there were no other options.