Where did Cain get his wife?

Q: How could all the races of the world come from one man and one woman? Did Cain and Abel marry their sisters?

A: If people are asking questions about the Bible, this one is sure to come up. The Bible doesn’t tell us, so it is speculation. Here are a couple options:

The Talmud (a history of commentary on the law by Jewish rabbis) tells us that Cain and Able were both born with twin sisters, who married the other brother. Yes, that is incest by later standards but, given the circumstances, it was necessary in the beginning.

In his book, The Science of God, Gerald Schroeder offers an interesting alternative view. He speculates that since Genesis says Adam was “made,” not “created” (meaning he was made out of something already existing), that the earth by this time was filled with...

hominids – pre-human creatures. When God announces His punishment on Cain for killing his brother, Genesis 4:15 says Cain “will be a restless wanderer on the earth, and whoever finds [him] will kill [him].” That suggests that there are other people in the world besides Cain, his parents and siblings. Schroeder suggests these are hominids, pre-human beings who may or may not have had spirit breathed into them by God as had happened when Adam was made. Again, this is speculation but it has biblical warrant in the language of Genesis. Interestingly, this would reconcile some aspects of evolutionary theory with the biblical account of creation. He does a much better job of describing this, so I suggest getting his book if you want to dig deeper.