Leviticus 18:6

"None of you shall approach to any that are near of kin to him, to uncover their nakedness: I am Jehovah. The nakedness of thy father, even the nakedness of thy mother, shalt thou not uncover: she is thy mother; thou shalt not uncover her nakedness. The nakedness of thy father's wife shalt thou not uncover; it is thy father's nakedness. The nakedness of thy sister, the daughter of thy father, or the daughter of thy mother, whether born at home, or born abroad, even their nakedness thou shalt not uncover. The nakedness of thy son's daughter, or of thy daughter's daughter, even their nakedness thou shalt not uncover: for theirs is thine own nakedness. The nakedness of thy father's wife's daughter, begotten of thy father, she is thy sister, thou shalt not uncover her nakedness. Thou shalt not uncover the nakedness of they father's sister: she is thy father's near kinswoman. Thou shalt not uncover the nakedness of thy mother's sister: for she is thy mother's near kinswoman. Thou shalt not uncover the nakedness of thy father's brother, thou shalt not approach to his wife: she is thine aunt. Thou shalt not uncover the nakedness of thy daughter-in-law: she is thy son's wife; thou shalt not uncover her nakedness. Thou shalt not uncover the nakedness of thy brother's wife: it is thy brother's nakedness. Thou shalt not uncover the nakedness of a woman and her daughter; thou shalt not take her son's daughter, or her daughter's daughter, to uncover her nakedness; they are near kinswomen: it is wickedness. And thou shalt not take a wife to her sister, to be a rival to her, to uncover her nakedness, besides the other in her life-time."

With minor exceptions, the stipulations here are clear enough and hardly need any comment.

"Uncover the nakedness of ..." This, as used here, simply means "to marry."[5] However, in the extended meaning, it has reference to sexual intercourse, which by implication is also included in the prohibitions here.

Here is a list of the prohibited marriages:

The all-embracing injunction was simply this: that all marriages of close of kin, whether by blood or by marriage, were strictly forbidden. The specific examples of it were then spelled out as follows:

Marriage was forbidden with:

(a) One's mother (Leviticus 18:7).

(b) A step-mother (Leviticus 18:8).

(c) A sister, a half-sister, or a step-sister (Leviticus 18:9).

(d) A granddaughter, whether by a son or a daughter (Leviticus 18:10).

(e) A half-sister (Leviticus 18:11).

(f) A paternal aunt (Leviticus 18:12).

(g) A maternal aunt (Leviticus 18:13).

(h) An aunt by marriage (Leviticus 18:14).

(i) A daughter-in-law (Leviticus 18:15).

(j) A sister-in-law (Leviticus 18:16).

(k) A granddaughter by marriage, whether by a son or a daughter (Leviticus 18:17).

(l) A marriage to the sister of one's wife during the wife's life-time (Leviticus 18:18).

This is the only prohibition that lies in uncertainty.

There is little that is hard to understand about this list. Any near kins-person, whether by blood or by marriage, is forbidden as a spouse. Of course, only the men are mentioned here as "taking to wife," but the same prohibition also existed with regard to any woman consenting to such illegal marriages. In those days, only the men were empowered to contract marriages, hence, the one-sided reference here.

"Thou shalt not take a wife to her sister, to be a rival to her ... in her life-time ..." There is a problem with understanding this. (1) It could be a downright prohibition of polygamy; (2) or a law against marrying sisters in a polygamous situation; or (3) a prohibition against marrying a wife's sister during the life-time of the wife, whether or not the wife had been divorced. Scholars differ rather dogmatically about the exact meaning, but it is safest to construe the passage as an outright condemnation of having a plurality of wives. Certainly the case of Jacob afforded tragic evidence enough of the tension and heartbreak that always came of such unions. Strangely enough, a number of the Hebrew patriarchs were in violation of God's rules announced here. Abraham married a half-sister, Sarah; Judah "uncovered the nakedness" of Tamar, a daughter-in-law; and Jacob had a polygamous family, also being married to sisters (because of the deception of Laban). Of course, subsequent to the entry of Israel into Canaan and the establishment of the monarchy, there followed the grossest kind of violation of these laws. David took his neighbor's wife and then had her husband murdered in a vain effort to cover up his sin. He also supported a royal harem. Solomon, with three hundred wives and seven hundred concubines, exhibited a life that was the public scandal of forty generations!

Some have considered it strange that marrying a daughter is not included in the list here, but, of course, that was covered in the blanket prohibition standing at the head of the list.

Civilized nations, in general, reflect the universal acceptance of these laws by including practically all of them in the statutes. In our own country, most states forbid marriage of first cousins, thus extending the restrictions here even more rigidly than they stand in this text.

The terminology of this chapter, by implication, teaches that all of the illegal marriages forbidden here were freely practiced in the pagan civilizations of Egypt and of Canaan. Ancient literature abounds with illustrations of this. "Among the Egyptians, marriage of sisters, and half-sisters was common, being practiced by the royal family, and encouraged by their pagan religion."[6] Among the Persians, Medes, Indians, Ethiopians, and Assyrians, marriages with mothers and daughters were allowed.[7]

Meyrick also favored us with this bit of history:

"The Roman code of forbidden marriages was nearly identical with the Mosaic code. It was different only by its inclusion of the grandmother and the niece with the prohibitions, and by omitting the brother's wife. The Emperor Claudius changed the law to allow him to marry a brother's daughter, Agrippina. Constantius vetoed that change and made the marriage of a niece a capital crime (355 A.D.). The marriage of first cousins was a disputed question, allowed at first by Roman law, condemned and outlawed by Theodosius (384 A.D.), but again allowed by Arcadius (404 A.D.). The historical Church accepted the position of Theodosius and forbade them, thus going beyond the Biblical prohibitions. The laws of many states are still in harmony with the Church's position."[8]

The prohibition in Leviticus 18:16 against marrying a brother's wife was not a contradiction of the Levirate law requiring it under certain circumstances. If one's brother died childless, the Levirate instruction required that he marry his deceased brother's wife and rear children to his brother's name and inheritance. The reason, perhaps, for that Divine exception to the rule here was based upon the principle of hereditary ownership of the land of Canaan by the various families of the Israelites, and was the keystone of their economy. With the coming of the monarchy, the greed and avarice of the kings of Israel succeeded ultimately in frustrating the Divine plan (Deuteronomy 25:5-10).

With regard to the penalties by which these regulations were enforced, the enigmatic statement in Leviticus 18:29, that, "Even the souls that do them shall be cut off from among their people," is disputed as to the exact meaning. In view of the dogmatic statement of Josephus that, "To those who were guilty of such insolent behavior, he (Moses) ordained death for their punishment,"[9] coupled with the death penalty invoked by Theodosius and others of antiquity, we are most likely justified in the conclusion that violation of these laws was indeed a capital offense.