Peter Pett's Commentary on the Bible
Leviticus 18:6-18
Relationships Within Families (Leviticus 18:6).
“None of you shall approach to any who are near of kin to him, to uncover their nakedness: I am Yahweh.”
Firstly the initial principle was laid down that there should be no sexual approaches among those who were of near kin, no approaches of the kind which were with a view to marriage and sexual relations. This was because Yahweh was Yahweh and disapproved of anything that could destroy family relationships, and knew what great dangers there were of sexual relationships doing this, and what tragedy they could bring about. This principle is now expanded in detail. For He wanted it known that His people were simply not expected to behave like that because they accepted Who and What He is.
That ‘marriage' is probably mainly in mind throughout, in that the person would seek to justify their behaviour by that means, comes out in that without legal marriage such behaviour should automatically have resulted in the death penalty anyway. Thus to have legitimacy they would have to marry the person involved. For when two had sexual relations they became one flesh. So it had to be made clear that in relation to those who are of near kin marriage is as bad as fornication and adultery.
On the other hand it might be argued that illicit sex within the family would be so hushed up, and so never revealed, that it had to be legislated against anyway, which explains the strong statements against it within close family relationships. Each man must be made to recognise that God would know and would punish what he did even if men could not. The point is being made that these activities are in fact forbidden under any circumstances, whether within marriage or not, and the emphasis is not so much on marriage as on the evil of sexual relations between such related people. They were wrong under any circumstance, and a professed marriage did not excuse them. To ‘uncover nakedness' refers to sexual intercourse.
From this point until Leviticus 18:23 the commands are all in the singular, stressing their application to each individual. He then again returns to the plural.
“The nakedness of your father, even the nakedness of your mother, you shall not uncover. She is your mother. You shall not uncover her nakedness.”
The first forbidden relationship for a man was with his own mother. To marry and/or have relations with his own mother, to uncover her nakedness, was clearly totally unseemly. To do so would be to utterly shame his father's name, with whom his mother was one flesh, and indeed his mother herself as made one with his father. He would be exposing his father's nakedness as Ham had done long before (Genesis 9:22). It would be totally unnatural and could not even be considered. Here God was enforcing the fact by statute.
Among other things such a relationship would dishonour the father with whom his wife had been one flesh, so that the revealing of her nakedness was the revealing of his; would distort positions of authority as the son, as the husband of the mother, would gain a status contrary to and in apposition to that of the firstborn son; and it could be seen as against nature. It also carried with it genetic dangers.
The sin of Lot's two daughters, which resulted in the birth of Ammon (Ben-ammi) and Moab (Genesis 19:30), can be compared to this although they literally uncovered their father's nakedness.
“The nakedness of your father's wife you shall not uncover. It is your father's nakedness.”
The next forbidden relationship was with any other wife or ex-wife of a man's father. This was forbidden because she and his father were one. Therefore to marry her and/or have sexual relations with her would be shaming his father. It is as if he had had sex with his father. He must not seek to take his father's place in this way. Furthermore it would again undermine authority.
And on top of that lust for a beautiful relative, if not absolutely forbidden, could cause all kinds of evil behaviour through the centuries, including convenient murder of the father. Without these laws forbidding it, any father with a very beautiful wife (like Sarah) might always be in danger of being murdered by his sons so that they could have her for themselves. But if legally they could not marry acceptably, much of the danger was removed. In Israel God was seeking to scotch that from the beginning by indicating that marriage to her would be out of the question. In this case the penalty for failure was to be death (Leviticus 20:11).
In fact a man lying with his father's wife was accursed by the law (Deuteronomy 27:23). He stood cursed before God. Such an incestuous relationship was engaged in by Reuben with Bilhah (Genesis 35:22), and by Absalom with his father's concubines or secondary wives (2 Samuel 16:22). The one lost his pre-eminence as the firstborn, the other his life. It was the sin that especially shocked Paul among the Corinthians (1 Corinthians 5:1), one not even thought of among the Gentiles.
“The nakedness of your sister, the daughter of your father, or the daughter of your mother, whether born at home, or born abroad, even their nakedness you shall not uncover.”
Marriage and/or sexual relations with a blood sister or half-blood sister were also forbidden, even if she had been born elsewhere. It is quite clear how impossible family life would have been if men could pressurise their own sisters. Family unity would have been impossible and no beautiful woman would have been safe to pursue an ordinary life (see 2 Samuel 13:12). But the regulations produced a mind set in Israel which helped to prevent all but the worst of men even thinking in this way. Those who did this were to be ‘cut off in the sight of the people' (Leviticus 20:17). They were cursed (Deuteronomy 27:22).
“Born abroad” may indicate an illegitimate daughter, but there may have been cases where a man had two families living separately.
When man was first in the world it is clear that such relationships did occur, but that was another matter, for then there was no alternative. All Adam's sons married their sisters, including Cain. It had to be so then, and genetic make-ups were simpler. But this was now forbidden.
“The nakedness of your son's daughter, or of your daughter's daughter, even their nakedness you shall not uncover: for theirs is your own nakedness.”
Marrying and having sexual relationships with grandchildren was also forbidden. Again families could have been destroyed by it, and the future of young children regularly blighted. It was vital that those who had responsibility for such children should honour them and not take advantage of them. They were intended to be their protectors! They should be able to trust their grandfathers absolutely, to watch over them and look after their best interests, not to be themselves pursuing them for sexual gratification. After all, they were a part of himself. How could he seek sexual relations with himself?
It would also distort lines of authority. If a child resulted a man could thereby find himself under the ‘authority' of his own daughter, which would make a mockery of authority.
“The nakedness of your father's wife's daughter, begotten of your father, she is your sister, you shall not uncover her nakedness.”
This confirms Leviticus 18:9, especially in the case of a half sister. Abraham seemingly went contrary to this rule, which had not, of course, then been laid out. Such intermarriage seems in his day to have been approved of in order to maintain the family aristocracy. Here it is forbidden. In Leviticus 20:17 the punishment is to be cut off in the sight of the people
“You shall not uncover the nakedness of your father's sister. She is your father's near kinswoman. You shall not uncover the nakedness of your mother's sister, for she is your mother's near kinswoman.”
Here aunts are forbidden as objects of lust, marriage and sexual relations. Again the protection of family unity, and lines of authority, and the necessity to ensure that those who should be protecting relatives left without protection did so with no ulterior motive, is in mind. This was especially so when they were children. A woman should be able to have confidence that her affectionate response to, and reliance on, her relatives did not result in unfortunate situations or coercion. She must be able to trust them. In this case the matter would be brought up for judgment and a suitable penalty be decided on, ‘they shall bear their iniquity' (Leviticus 20:19). It was thus not seen as quite such a serious offence. In fact Amram, Moses' father/ancestor, married his father's sister (Exodus 6:20).
“You shall not uncover the nakedness of your father's brother, you shall not approach his wife. She is your aunt.”
The prohibition also includes aunts through marriage. Marrying and having sexual relations with an uncle's wife would be a shaming of one's uncle, whether alive or dead. This also would be judged by the courts, but in this case, additionally, God would punish it directly by making them childless (Leviticus 20:20).
“You shall not uncover the nakedness of your daughter-in-law. She is your son's wife. You shall not uncover her nakedness.”
A daughter-in-law, a son's wife, is forbidden for marriage and sexual relations to a father. The daughter-in-law is one flesh with his son. Thus the father must honour what is his son's, and not shame his son. Among other things the inheritance problems and the resulting hatreds and rivalries could have been horrendous. The point was that a son should be able to trust his father in such matters absolutely and be confident that he would not complicate or take advantage of his family if he died or divorced, but would act only in their best interests. The punishment in this case is death because it has ‘wrought confusion' (Leviticus 20:12). It is intermixing two generations.
“You shall not uncover the nakedness of your brother's wife. It is your brother's nakedness.”
Nor shall one brother marry and have sexual relations with his brother's wife, with a view to her becoming his wife and bearing children to him, whether his brother is dead or divorced, for to do so would be to shame his brother, with whom his wife was ‘one', and destroy family relationships. This was the sin for which John the Baptiser rebuked Herod Antipas. This is not forbidding levirate marriage. In that case the brother was dead and the aim was to honour his brother, and raise up children in his name. In that case also the children were seen as the brother's. That was not a case of family conflict, but of family cooperation. The penalty for not fulfilling the levirate law but taking the wife for himself would be that the marriage went childless (Leviticus 20:21).
It may well be that in levirate ‘marriage' the sexual relations were deliberately carried out more discreetly.
“You shall not uncover the nakedness of a woman and her daughter, you shall not take her son's daughter, or her daughter's daughter, to uncover her nakedness. They are near kinswomen. It is wickedness (prostitution).”
To marry and have sexual relations with both a mother and her daughter, or with a mother and her granddaughter, was forbidden. They were near kinswomen. The tensions that would arise and the pain that could be caused are not to be contemplated, and no man should so take advantage of his position. He should be aware of the great harm and misery that could result. It was to treat them like prostitutes just available for his lust, have no regard for their deeper feelings and play havoc with relationships. And once again lines of authority and inheritance would be blurred. This was another case where death was the penalty for both (Leviticus 20:14). For a man to lie with his mother-in-law was to be cursed (Deuteronomy 27:23).
“And you shall not take a wife to her sister, to be a rival to her, to uncover her nakedness, besides the other in her lifetime.”
Nor should a man marry one sister after another while they were both alive. In a polygamous marriage wives were rivals, and this would be to make two sisters rivals and possibly antagonistic to each other, and would be to destroy the natural love between them. This was not to be contemplated. Family love was important to God, the Supreme Father. This was, of course, what Jacob did and it caused great grief of heart.
In all these prohibitions we see God's concern that non-sexual, loving relationships and responsibilities within families were of prime importance, that lines of authority should be clearly maintained, that inheritance questions must not be complicated unduly, and that these things must come before all others, so that lust especially must not be in a position to destroy them. They reveal a deep sense of the current and counter-currents that sexual feelings could cause within close family units, and provided the standards by which they should be assessed and dealt with.
However, they also served another purpose. The inter-marriage of relatives who are in too close a relation to each other can also be the cause of an increase in birth defects and, if continued in through the generations, can result in a lack of vitality and vigour in the strain. That also is therefore not something to be advised.