Last week, Ken Ham of Answers in Genesis spoke at the Family Research Council's "Watchmen on the Wall" conference where he warned that the failure to embrace a literal interpretation of the Book of Genesis is undermining "the doctrine of marriage" and leading to things like gay marriage.
So I decided to reread Genesis. Ham's assertion that a literal interpretation was required in order to understand the true nature of biblical marriage was in the forefront of my mind as I began working my way through Genesis, especially once I realized how much polygamy and incest the book contained.
In fact, outside of Adam and Eve, and Noah and his wife, just about every major patriarch engaged in either polygamy or some form of incest, and often both.
According to Genesis 16, Abraham slept with and married his wife's Sarah's slave because Sarah was was unable to bear children. On top of that, according to Genesis 20, Sarah was also Abraham's half-sister and he later took at least one more wife.
Abraham's son Issac was married to Rebekah, who, according to Genesis 24, was the daughter of the son of Abraham’s brother, which would make Rebekah the daughter of Issac's cousin, or Issac's first cousin, once removed.
Rebekah then gave birth to Esau and Jacob. According to Genesis 26, Esau married two Hittite women and then later took a third wife while Jacob married the daughters of his mother's brother, his first cousins, named Leah and Rachel. Rachel was unable to bear children and so gave Jacob her servant to sleep with and take as a wife, to which Leah responded by likewise giving Jacob her servant for a wife.
In addition to these arrangements, Genesis 38 tells the story of Judah sleeping with and impregnating his daughter-in-law while Genesis 19 tells the story of God's destruction of Sodom and Gomorrah where only Lot and his two daughters were saved ... after which Lot's daughters got their father drunk and slept with him and became pregnant.
One of the arguments we hear most often from the Religious Right is that changing "the biblical definition of marriage" by allowing gay marriage will lead to things like polygamy and incest ... which is odd considering that, according to the Book of Genesis, polygamy and incest were predominant forms of marriage.