Cain’s wife was a member of Adam’s family and probably Cain’s sister.
There are only limited details on the name and character of Cain’s wife. The only mention of Cain’s wife in the Bible is in Genesis 4:17, where Cain and his wife had a son. They soon named a city after him. The Bible does say that Adam and Eve had more children besides Cain and Abel (Genesis 5:4). No doubt it was one of these daughters that Cain took for a wife.
The custom of brothers marrying sisters was common as late as the time of Abraham, for in Genesis 20:12 we find that Abraham married his half-sister. In that period of the world men and women had not become diseased, deformed and mentally deficient as they are today. Because of this condition in many families at the present time, close intermarriage between members of the same family is not recommended.
In Leviticus 18:6-17, Moses prohibited close intermarriages between members of the same family.
Genesis chapter 4 tells the story of Cain and his wife. The highlights of this chapter include:
Please note: there are two Enoch’s mentioned in Genesis. One is a descendant of Cain (Genesis 4:17) and the other a descendant of Seth (Genesis 5:19, 21-24).
The chapter ends with the birth of Seth, Adam and Eve’s son. “And Adam knew his wife again, and she bore a son and named him Seth, ‘For God has appointed another seed for me instead of Abel, whom Cain killed’” (Genesis 4:25).