“Why did God allow incest in the Bible?”……There are numerous examples of incest in the Bible. The most commonly thought-of examples are the sons/daughters of Adam and Eve (Genesis 4), Abraham marrying his half-sister Sarah

Genesis 20:12

And she really is my sister, for we both have the same father, but different mothers. And I married her.

Genesis 19

Lot and his daughters

Exodus 6:20

Moses' father Amram who married his aunt Jochebed

Amram married his father's sister Jochebed, and she gave birth to his sons, Aaron and Moses. (Amram lived to be 137 years old.)

2 Samuel 13

David's son Amnon with his half-sister Tamar.

It is important to note, however, that in two of the above instances (Tamar and Lot) one of the parties involved was an unwilling participant in the incest.…It is important to distinguish between incestuous relationships prior to God commanding against them and incest that occurred after God's commands had been revealed.

Leviticus 18:6-18…"You must never have sexual relations with a close relative, for I am the Lord.… "Do not violate your father by having sexual relations with your mother. She is your mother; you must not have sexual relations with her.… "Do not have sexual relations with any of your father's wives, for this would violate your father.… "Do not have sexual relations with your sister or half sister, whether she is your father's daughter or your mother's daughter, whether she was born into your household or someone else's.… "Do not have sexual relations with your granddaughter, whether she is your son's daughter or your daughter's daughter, for this would violate yourself.…"Do not have sexual relations with your stepsister, the daughter of any of your father's wives, for she is your sister.… "Do not have sexual relations with your father's sister, for she is your father's close relative.…"Do not have sexual relations with your mother's sister, for she is your mother's close relative.…"Do not violate your uncle, your father's brother, by having sexual relations with his wife, for she is your aunt.…"Do not have sexual relations with your daughter-in-law; she is your son's wife, so you must not have sexual relations with her.…"Do not have sexual relations with your brother's wife, for this would violate your brother.…"Do not have sexual relations with both a woman and her daughter. And do not take her granddaughter, whether her son's daughter or her daughter's daughter, and have sexual relations with her. They are close relatives, and this would be a wicked act.…"While your wife is living, do not marry her sister and have sexual relations with her, for they would be rivals.

Until God commanded against it, it was not incest. It was just marrying a close relative. It is undeniable that God allowed incest in the early centuries of humanity. If Adam and Eve were indeed the only two human beings God created, their sons and daughters would have had no other choice but to marry and reproduce with their siblings and close relatives.

The second generation would have had to marry their cousins, just as after the flood the grandchildren of Noah would have had to intermarry amongst their cousins.

The reason incest is so strongly discouraged in the world today is the understanding that reproduction between closely related individuals has a much higher risk of causing genetic abnormalities.

In the early days of humanity, though, this was not a risk due to the fact that the human genetic code was relatively free of defects.……It seems, then, that by the time of Moses, the human genetic code had become polluted enough that close intermarriage was no longer safe. So, God commanded against sexual relations with siblings, half-siblings, parents, and aunts/uncles. It was not until many centuries later that humanity discovered the genetic reason that incest is unsafe and unwise.

While the idea of incest is disgusting and abhorrent to us today, as it should be, we have to remember why it is sinful, that is, the genetic problems. Since this was not an issue in the early centuries of humanity, what occurred between Adam and Eve's children, Abraham and Sarah, and Amram and Jochebed, should not be viewed as incest.

Again, the key point is that sexual relations between close relatives must be viewed differently pre-Law and post-Law.

It did not become "incest" until God commanded against it.………