Komentarz do Kapłańska 18:18

‎ אל אחתה ‎[NEITHER SHALT THOU TAKE A WIFE] TO HER SISTER — both at the same time.

AND THOU SHALT NOT TAKE A WOMAN TO HER SISTER, TO BE A RIVAL TO HER, TO UNCOVER HER NAKEDNESS, BESIDE THE OTHER IN HER LIFETIME. Here Scripture explains the reason for the prohibition, stating that it is not proper for you to take a woman in addition to her sister, to be a rival one to another, for it is fitting that they love one another and not be rivals. He did not say so with respect to a woman and her daughter,²⁹⁶Verse 17. or a woman and her mother,²⁸⁷Further, 20:14. because they are “near of flesh” and therefore forbidden even after the death of the other [while in the case of two sisters, it is only during the lifetime of his wife, even if she is already divorced from him, that he may not marry her sister].

לא תקח לצרור, the Torah means that were it not for the competitive hostility which would result by the two sisters competing for the love of the same man, there would not have been a biological, genetic reason for forbidding such a union. Proof that this is the guiding motivation of the Torah is the fact that after the death of one sister, the surviving husband may marry the surviving sister.

לצרור, similar to Samuel I 1,6 וכעסתה צרתה, “she deliberately angered her competitor Chanah, also wife of Elkanah. When a man has two wives, each is considered as a hostile competitor, צרה to the other.

ואשה אל אחותה לא תקח לצרור,” and you must not marry your wife’s sister to make them rivals.” Until you married your wife’s sister, these sisters maintained a very warm relationship with one another. As soon as you provided the basis for jealousy among them by marrying both, you broke up this relationship and turned them into enemies, each vying for your favour. [We only need to think of Rachel and Leah to know the truth of that piece of psychology. Ed.] This same consideration does not apply when a man treats both a mother and her daughter as his wife, even though in terms of DNA the relationship between mother and daughter is closer than that between two sisters. This is borne out by the fact that one may marry the sister of one’s wife if one’s wife has died, something that is forbidden in the case of a mother who is one’s wife dying and one wants to marry her daughter.

ואשה אל אחותה לא תקח, “you must not marry a woman’s sister in addition to her.” The word לא תקח, normally applied to a legal union, i.e. marriage, in this instance means “do not sleep with her.” There are occasions when sexual union is described as ביאה whereas on other occasions it is described as שכיבה; on still other occasions it is referred to as ידיעה, whereas here it is phrased as קיחה. The reason that the Torah employs words other than קיחה to describe the same act is to ensure that we do not think that only a formal union such as by means of קידושין, a betrothal involving the bride receiving something of value has been forbidden whereas an informal union of two consenting parties is permitted. Seeing that a legal union with one’s wife’s sister while the former is alive is altogether impossible, the word לא תקח clearly does not describe what is impossible but what is possible, i.e. a sexual union without the benefit of marriage. Chapter 20,17 as well as chapter 20,14 where the Torah uses the word קיחה refers to sexual union without the benefit of a legal contract.

Both as one. As it was learnt in the Mishnah, “Someone who marries a woman and her daughter, or a woman and her sister [together] at one time, neither are married [to him] as it is written, ’You shall not take a woman and her sister,’ [meaning], you shall have no ’taking’ [marriage] even to one of them.” The meaning of אל אחותה [lit. to her sister] is like על and means עם אחותה, “with her sister.” This is similar to על נשיו (Bereishis 28:9), which means “with his wives.”

ואשה אל אחותה, “and a woman (as a wife) in addition to her sister;” this construction is also found in “ אל חלליהם, in Joshua 13,22, where it means: “together with the others who had been slain.”

לצרר is connected with the word ,צרה — a rival (cf. I Samuel 1:6). Thus the verse signifies “thou shalt not take a wife to her sister", to make (i. e. making) the one the rival of the other.

As long as [his former wife] is alive. (Devek Tov) Because if not, why write “in her lifetime?” The verse already wrote “with her sister” which implies [taking] both together as one.

לא תקח לצרור, “you must not marry to become a rival;” the result would be that both these women (the sisters) would be widows in the house of their husbands while the husband is alive, as he is forbidden to have marital relations with either one of them.

בחייה DURING HER LIFE-TIME — This teaches you that if he divorced her (his wife) he is not allowed to marry her sister so long as she (the former) is still living (Yevamot 8b).

לגלות ערותה, “to reveal her nakedness;” to the second one while both are alive.

עליה, “with her;” we find the expression על used in the sense of “with,” also Leviticus 25,31 על שדה הארץ יחשב, “they will be considered as belonging with the fields of the country.