This question has been bandied about for centuries by well intentioned scholars, skeptics and guys looking for honest answers that don’t involve speed-dating.
Creationists say she was a close relative. theistic evolutionaries claim she was obviously a woman from another clan. No one from either camp has able to explain how they met. My money is on Pre-Christian mingle.

Not McCain’s wife! I said Cain’s wife.
Those who hold to the young-earth position claim that Cain’s wife was possibly a sister or niece. the reasons given for this include the theological stance that any mysterious “other” woman would be precisely that – a woman who was “other than” human, not related to Adam. And as the creationist logic spins, anyone not descended from Adam ( if it were possible) isn’t capable of being saved because people not of Adam don’t have a soul. This is theory A. The upside of theory A is that, if true, we don’t have to worry about running into neanderthals in heaven. Theory A is the favored position by those who believe that Genesis is the only source of true stories about the ancient world.
But there is another take on this puzzle. Theory B takes a wildly different view of origins while still holding to a high view of Genesis. Cain’s wife isn’t so much a problem, as she is the answer. By inserting her into the Biblical record, the writers of Genesis (Moses himself or his people – yes, Moses had people) are telling us straight up that there were other stories being played out offstage, while we are following the drama with Adam’s family…
In theory B, Cain’s wife was from a neighbouring village with a different family tree. In theory B, Cain’s wife was just a small town girl… Living in a lonely world… Until she met the love of her life, and self-confessed murderer, Cain. Sally (not her real name) was not really the girl next door because there were no actual neighbours in Cain’s neighbourhood. you would think it would be easy to find buyers for the property right next to the Garden of Eden, but apparently “location location location!” didn’t become the cry of real estate agents until well after the fall.
Pre-Adamites, as these soulless subhumans have come to be known in Genesis debating circles, refer to any race of people that appears to pre-date Adam and Eve. If you grew up in the Christian bubble like I did, pre-Adamites were the stuff of legend. Un-provable characters that we could never know anything about unless we started believing what the scientists were telling us about human origins. And there’s the rub. How do we accept the claims of the anthropologists and linguistics experts without losing our grip on Genesis? How do we ‘give’ on the issue of ancient man without caving on our adherence to the Biblical record.
I return to Cain’s wife as major a hint to this puzzle and there’s a model from geometry that I often use to describe the solution. Many people struggling with this puzzle view all of history as a Funnel. Check out my earlier post on FUNNEL VISION and let me know what you think.
It says in Genesis that Adam lived for hundreds of years and begat sons and daughters, yet no other children are mentioned until Seth came along when Cain and Abel were fully grown. Does that mean there were no other children born to Adam and Eve until then? Really? Did they stop at two kids even though God commanded them to increase, meaning you know what?
A man and woman in what today would be paradise, even though it was not the Garden, no birth control, no industrial pollution at all and so healthy they were able to live for hundreds of years, and no kids for decades?
What’s wrong with this picture?
If the bible does not explicitly say Adam and Eve had no other children until Cain, then can we not make some sincere assumptions without the risk of heresy?
I think the short answer is that Cain found one of his fourth cousins several times removed for his bride.
There was no law at that time other than the one they broke in the Garden, so, as sick as this sounds in today’s culture and times, Cain could have freely taken his own sister to wed without raising eyebrows.
Furthermore, the gene pool was different then (are there any today like Esau, red and hairy all over?) than it is now and the genetically-associated problems with children born to siblings would probably not be a problem way, way back then.
Hi Jim,
You bring up a lot of great points and I am very familiar with these explanations. I don’t have any problem with Adam and Eve having other children, however just because the law hadn’t been given the the Moses/Charleton Heston sense (with tablets of stone) doesn’t mean that the law didn’t apply. This is a broader theological question. If God doesn’t say ‘thou shalt not covet’ – is coveting a good thing. Same with incest.
Also, to say the gene pool was different than today is a statement that needs to be backed up with science and in a young earth scenario, there isn’t any science that fits the timeline.