Because it refers to creating at least one man on day 6, with "in the image of God he created him"?
We know Eve was the mother of all, because that is clearly stated in 3:20. A multi-step logical deduction from other verses cannot be taken to contradict that clear statement. However Adam, Eve and the rest of mankind were created must be consistent with the fact that Eve is the mother of all. If the interpretation contradicts that clear fact, the interpretation is wrong.
Which means that either
- Adam was created on day 3, and 1:26-27 summarises the previous creation of Adam and present creation of Eve (it says man was created then, but that's not completely accurate but close enough as a summary statement), or
- Adam and Eve were created on day 6, and chapter 2 contains similar summary statements (when it says God formed the animals, it doesn't mean He created them right then, but rather that He had formed them previously and then brought them to Adam, but it just says he made the animals as a summary statement because the focus is on man).
Either way you've got some passage somewhere that is a summary statement rather than being chronologically precise. And that's ok, in my mind.
Excellent summary! Now to the question of how we got to this point, Levitical Law clearly states that a man is not allowed to have sexual relations with both a woman and her daughter. Interestingly enough, it also states that you cannot marry your sister! No doubt, Cain married his sis, and according to the Book of Jubilees FWIW, so did Seth. Obviously, that was a different dispensation, and the human race could not have gone anywhere without incest occurring in one form or another. I love how the evolutionist resorts to Argument From Personal Disgust, to imply that 6 day literal creation could not have taken place! Having said that,
@steve may be onto something. Sure God only created Eve for Adam, but there is nothing in Scripture that says that he didn't marry one of his daughters. I would love to see the anti-polys try to explain how it is impossible for Adam to have had more than one wife, but yet probable that his sons married their sisters.
I am imagining this exchange:
Anti P: Adam only had one wife.
Pro P: How do you know that?
Anti P: Well, God only made one wife for him.
Pro P: But Scripture tells us that he had sons and daughters.
Anti P: Yeah, but he didn't marry any of his daughters!
Pro P; How do you know that?
Anti P: Well, that is incest!
Pro P: Well, who did his sons marry?
Anti P: Their sisters of course!
Pro P: Well, that is incest as well!
Anti P: But God hadn't given the laws against incest at that time!
Pro P: You just made my point!
Anti P: Well, the Bible doesn't SAY that he married any of his daughters.
Pro P: Sure! It also doesn't SAY that his sons married their sisters. Maybe they married their nieces! The point is, you cannot possibly KNOW that Adam had only one wife.
OR
Anti P: God only made one wife for Adam.
Pro P: Well then, you are assuming that he didn't marry any of his daughters.
Anti P: Of COURSE he didn't marry any of his daughters; that would be WRONG!
Pro P: Wouldn't it have also been wrong for Adam's sons to marry their own sisters? I mean, who do you think they married?