ABC:Genesis 17

Verse 10
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Circumcision

“This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised."

Genesis 17:10 This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised.

“... if ye be circumcised, Christ shall profit you nothing.”

Galatians 5:2 Behold, I Paul say unto you, that if ye be circumcised, Christ shall profit you nothing.

First of all, Paul was not speaking generally or saying that circumcision is wrong for Christians. Rather, he was addressing Galatian Greek Christians who were being falsely told by Jews that to be saved they had to follow all the Old Testament Law and be circumcised. (Gal. 6:12-13) Paul in his letter to the Galatians points out that the Old Covenant, the Law, while it was a just law, could not save or make people perfect (Gal. 3:11); had there been salvation in it there would have been no need for Jesus to come. (Gal. 2:21) Paul points out that good deeds cannot save a person, only the mercy available through Jesus because of His sacrifice for us. Paul's point was that for the Greek Christians to get circumcised late in life just to try and become righteous through the Law would be to effectively reject the tenets of their Christian faith, that they were saved through God's mercy because of what Jesus did, rather than their own works. (Gal. 2:16-18) Their sin was not being circumcised, but attempting to be justified through the Law after they had already been justified through faith in Jesus. (Gal. 5:4) Paul ultimately concludes that it does not matter for purposes of righteousness before God whether or not one is circumcised. (Gal. 6:15)

Circumcision was commanded in the Old Testament for medical reasons, as were many other commandments. It is now recognized that circumcision provides numerous medical advantages to children, protecting them against disease, including a decreased risk of urinary tract infections, a reduced risk of Sexually Transmitted Diseases, protection against penile cancer, and a reduced risk of cervical cancer to female partners. As such, it was a useful and necessary commandment for Israelites to follow under the Old Covenant long before the advent of modern medicine (Heb. 9:9-10), but under the New Testament is de-emphasized by Paul because Jewish legalists were falsely teaching that following it was necessary for salvation and acceptance by God.

Verse 15
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Genesis 17:15 And God said unto Abraham, As for Sarai thy wife, thou shalt not call her name Sarai, but Sarah shall her name be. 16 And I will bless her, and give thee a son also of her: yea, I will bless her, and she shall be a mother of nations; kings of people shall be of her.

Abraham marries his half-sister. God blesses the union in Genesis 22:17.

Leviticus 20:17 And if a man shall take his sister, his father's daughter, or his mother's daughter, and see her nakedness, and she see his nakedness; it is a wicked thing; and they shall be cut off in the sight of their people: he hath uncovered his sister's nakedness; he shall bear his iniquity.

Incest is a disgrace. Deuteronomy 27:22 Cursed be he that lieth with his sister, the daughter of his father, or the daughter of his mother. And all the people shall say, Amen. 23 Cursed be he that lieth with his mother in law. And all the people shall say, Amen.

The perpetrator is "cursed."


 * See also Pre-Flood Longevity

As Romans 5:13 says, "sin is not imputed when there is no law." Before the time of Moses there was no necessity for a law against incest because such vast lifespans made for very different family units, and incest was thus not wrong in the same way it is today. The commandment against incest was not given until the time of Moses because incest was not wrong before that, since people lived such extraordinarily long lives, centuries longer than we do today. Technically it wasn't incest by today's standards since early humans each had lifespans of 900 years (Genesis 5).

Incest was only declared wrong by the time of Moses when people had average lifespans of 70 years (Psalms 90:10) and God when the Flood started began reducing the average lifespan to 120 years (Genesis 6:3). Lifespans did not reach this point until about the time of Moses, who lived exactly the 120 years specified. (Deuteronomy 34:7) Incest today is considered wrong, as it should be, because children who grow up with one another as part of the same family should not have sexual relationships. However, ancient people like Noah's family lived centuries upon centuries and could be born many centuries apart in age from their siblings, old enough by today's standards to be the great, great, great, great, great, great, great grandparents of their brothers and sisters.

In the case of Abraham, he lived to be 175 years old, whereas his half-sister and wife Sarah lived to be 127 years old. (Genesis 25:7, Genesis 23:1-2) Both lived longer lives than anyone today can live. People lived such long lives at the time that Abraham's great, great, great, great, great, great, great, great grandfather, Noah himself, did not die until 18 years after Abraham was born, at the ripe age of 950 years old! Under the Biblical model, such ancient patriarchs could have siblings considerably older and more distant in relation than is seen today, which is why the commandment against incest was not yet given, and incest at the time was not wrong.