I remember all the way back to my middle school days wondering how humanity could come from Adam and Eve. It seemed inevitable that either (1) Adam had to reproduce with some of his own daughters and/or (2) Adam’s sons and daughters reproduced amongst themselves. I always thought that it was a bit gross either way.
I was told that I need to read through the Book of Jubilees if I am interested in the Jewish worldview of the Second Temple period. I am glad that I have begun doing so, because it answers all my childhood questions about how Moses knew what happened at creation (see here), how the serpent talked (see here), and how the human race reproduced:
“And Cain took ’Âwân his sister to be his wife and she bare him Enoch ” (IV.9)
Gross now; essential then. Thank you Book of Jubilees!
the archives near Emmaus 
“Cain hated his brother, but loved his sister.” That made me laugh out loud! 🙂
I do what I can! 🙂
It depends if you believe in a literal Adam and Eve of if humanity actually existed elsewhere and God took Adam and Eve from them and placed them into the garden….
@Craig: Of course it does. I am not quoting it so much to make a point for one side or the other in the current debate over the literalness of Adam, but rather to show how Second Temple Jews explained something I used to ponder as a kid.
Gotcha! My bad.
I enjoy reading a variety of midrash and how it relates to the editing of the Scriptures….if indeed the Pentateuch was edited within the post exilic period – its important to understand that era’s thinking.
No worries. Indeed, it is very important to know that era’s thinking.
So of the targums say Cain killed Abel because he was jealous that Abel’s sister/wife was prettier than his.
@John…that is interesting. I nearly tongue in cheek said that Able was killed for his wife…
Within a post exilic editorial reduction it seems that it is nearly a repeat of King David and Bathsheeba.
@John: I guess Abel got the pretty sister!