Themes in Genesis: Incest

There is a lot of incest in the book of Genesis.
-Nahor married his niece.
-Abraham was married to his half sister, or possibly his niece.
-Lot's daughters had sex with their dad.
-Isaac married his cousin.
-Esau married his cousin.
-Jacob married 2 of his cousins.
-Judah had sex with his daughter-in-law.

REASONS FOR INCEST:

-Having a child through incest was preferred to having no children at all.
-When Lot's daughters had children from an incestrial affair, I am left to wonder if the story was used to dishonor the 2 nations that resulted from the two children - the Moabites and the Ammonites.
-People trusted relatives and preferred keeping to them in marriage.  Abraham, Isaac and Jacob were nomads, traveling from place to place; so they didn't build enduring relationships with people in the towns nearby.

The book of Genesis clearly reveals that Abraham and Isaac distrusted and feared outsiders.  When Abraham went from place to place, he occasionally went into the towns nearby.  When he was with his wife during these visits, he told her to tell people that she was his sister.  He feared that the town's people would kill him if they knew she was his wife, because they would want her and want to take her away from him by force.  In reality, the town's people held to much better morals than Abraham gave them credit for.  Abraham's fear of the outsider was unfounded and unreasonable.  On two occasions he was rebuked for his scam and accused of unethical behavior by those very town's people he believed would be immoral.

This fear of the outsider continued in Abraham's son Isaac, and probably in Jacob.  When Esau married 2 girls from local towns, his mother did not bond with them, but rather complained about them to her husband.  When Esau realized this, he went and married one of his cousins from his father's side.

INCEST AND THE LAW OF MOSES:

Genesis appears to act as a demonstration or background of the type of incest that was not allowed in the Law. With the exception of marrying cousins, every one of these practices mentioned above were made illegal in the Law of Moses.

Genesis offers us a window into the past; it gives us examples of and the reasons why people having sex with near relatives. And why were these condemned by Moses' Law? There was no reason given.  But I suspect that it is because that by Moses' time Israel was no longer a nomadic tribe becoming numerous; and there were a large amount of marriageable people that held similar values and culture.