1.3. Prohibitions of Marriage Within Close Degrees of Kinship. The Philosophical-Psychological Basis of Such Prohibitions

The provisions of Mosaic legislation on marital unions of Israelites among themselves are of a different character. Just as with respect to marital unions with foreigners the prohibitions increase in accordance with the diminishing degree of religious and tribal kinship, so here—with respect to marital unions among Israelites themselves—conversely, the prohibitions increase in accordance with the increasing degree of kinship. The distinguished scholar of the history and spirit of the Hebrew people, Ewald, remarks on this subject: “In respect to the prohibition of marital unions with close kindred, the religion of Jehovah (Iahvethum) is stricter than all ancient religions. The reason for this must be sought in a better understanding of the very essence of marriage. Marriage is to unite what is separate and yet, by its ultimate purpose, was created for each other, and therefore must enter into a firm union and become the beginning of a new household. The society established through marriage ought to be, as it were, entirely different from that which already existed before it—bound by a community of blood, birth, and shared life; a society bound by a love entirely distinct from familial love. Therefore, the deeper the tribal division between clans and tribes, the more freely and vigorously from their marital relations new life can develop—life free from the one-sidedness and weakness of excessive similarity. What is most divided appears to strive all the more powerfully toward union, to supplement its own one-sidedness with the contrasting qualities it lacks in the other.” The provisions defining marital relations among Israelites themselves may be divided into general provisions—having validity for the entire people—and special provisions, intended for exceptional cases.

The general provisions consist almost exclusively of prohibitions on marital unions at various close degrees of kinship. They are fairly numerous and are set out primarily in the book of Leviticus (Lev. 18:6 and following; Lev. 20:11 and following) and in Deuteronomy (Deut. 27:20, 22–23). Without going into all the details of these provisions, we shall examine the most characteristic among them—those that most fully express the spirit of the law.

The detailed exposition of provisions concerning marital unions at various degrees of kinship is prefaced in the law by a general definition, according to which “none of you shall approach any blood relative (scheer basero) to uncover nakedness” (Lev. 18:6). The Hebrew expression used here—scheer basero—is ordinarily referred to blood kinship. The etymological meaning of the word scheer is not definitively established. Some scholars find in it a connection with schaar—to remain (from which scheer = a remnant of something, a part of something common). This explanation appears to find support in the literal Hebrew text and in the general biblical view, according to which all kinship is regarded as if constituting a single flesh, so that each member of a kinship group considers the remaining members of the same kinship as it were members of their own flesh. Others simply assign to it the meaning of “flesh,” which is more straightforward and more readily explicable in the present case. But whatever of these two meanings we choose, in any case its usage (Lev. 18:12–13, 17; 20:19; Num. 27:11) inseparably carries the concept of blood kinship. The expression basar, literally meaning “flesh” or “body,” is also used in the sense of blood kinship (Gen. 32:14; 37:27; Judg. 9:2; 2 Sam. 5:1; 1 Chron. 11:1). Both words scheer basar are used together in (Lev. 25:49) in the sense of mishpachah—“family” or its members bound to one another by ties of blood kinship. A similar meaning the expression carries in the passage under examination. In literal translation, scheer basero means “the remaining parts of one’s own flesh” or “flesh of one’s flesh.” Its meaning in the sense of blood kinship becomes clear from comparison with the expression of Adam spoken of the wife created from his flesh: “This is bone of my bones and flesh of my flesh” (Gen. 2:23)—an expression used to denote the closest blood bond or kinship. The other expression used in the provision under examination, “to uncover nakedness,” is according to Saalschütz not identical with the word beschlafen—“to lie with” (in the Old Slavonic rendering), meaning the simple act of carnal union, for which there is a separate word (Lev. 18:20, 23, and elsewhere). It is broader than the latter and denotes marital relations in general—which is evident from its equivalent substitution by another expression: “to take a wife” (Lev. 18:18). In a closer sense, as applied to the provisions in question, it denotes an unlawful marriage, criminal incest. This is the understanding we shall keep in mind in the further exposition of the provisions.

The regulations under consideration, in relation to various degrees and lines of kinship, fall into three separate groups. The first group, encompassing verses 7–13 of chapter 18 of the Book of Leviticus (Lev. 18:7–13), contains regulations concerning blood kinship in the direct line. These regulations are as follows:

1) “You shall not uncover the nakedness of your father and the nakedness of your mother. She is your mother; you shall not uncover her nakedness.” In this regulation, which is clear in itself, the expression “to uncover the nakedness of one’s father” deserves attention. It gives some occasion to suppose incest of a daughter with her father, all the more so because this crime is nowhere else mentioned. But such a supposition is unfounded: if the legislator here had in mind the crime of a father with his daughter, then by the accepted formula he would have directed the prohibition toward the male—toward the father—which is not the case here. The legislator does not mention this crime because the unlawfulness of such incest is self-evident, and therefore the legislator does not presuppose its commission. (For the same reason, patricide or matricide is not mentioned either (Exod. 21:15).) According to the biblical usage of this expression, its meaning is that a son must not defile his father’s bed by committing adultery with his wives, and thereby uncover his nakedness (Deut. 27:20).

2) “You shall not uncover the nakedness of your sister, the daughter of your father or the daughter of your mother, whether born at home or born outside” (Lev. 18:9). Here the expression “born at home or born outside” is not entirely clear. Some scholars understand this to mean the daughter of the father’s concubine. But such an understanding does not correspond to the literal precision of the expression. It is more consistent with the substance of the matter to understand this expression to mean, first of all, a full sister (born “in that same house” in which the brother was born, i.e., from the same father and mother), and then a half-sister, born “outside that house” in which the brother was born, i.e., from a different mother who bore her while she was still married to another man, in another house. But with such an understanding, the regulation of verse 11 (Lev. 18:11), which reads as follows, seems to become purposeless:

3) “You shall not uncover the nakedness of your father’s wife’s daughter, begotten by your father—she is your sister—you shall not uncover her nakedness.” This appears to coincide entirely with the second half of the previous regulation. Knobel tries to find a difference between verses 9 and 11 (Lev. 18:9–10) in that verse 9 refers to a half-sister, whether born in lawful wedlock or outside it, while verse 11 (Lev. 18:11), along with a half-sister, also refers to a full sister, since in his view the expression “the wife of the father” equally denotes both the natural mother and the stepmother. But such an understanding is scarcely well-grounded, all the more so because the expression “wife of the father” is a characteristic expression for distinguishing a stepmother from a mother. More plausible is the supposition that in verse 9 (Lev. 18:9) both a half-sister and a full sister are intended, while in verse 11 (Lev. 18:11) only a half-sister. Such an understanding is more consistent both with the very method of exposition of the regulations under consideration, by which the legislator proceeds from the general to the particular, and with the order of degrees of kinship, by which the legislator first examines closer degrees and then moves on to more distant ones.

4) “You shall not uncover the nakedness of your son’s daughter (a granddaughter through a son) or your daughter’s daughter (a granddaughter through a daughter); you shall not uncover their nakedness, for their nakedness is your own” (Lev. 18:10), that is, they proceeded from your nakedness, so that in uncovering their nakedness, you would be uncovering your own nakedness.

5) “You shall not uncover the nakedness of your father’s sister (a paternal aunt); she is your father’s blood relative” (Lev. 18:12).

6) “You shall not uncover the nakedness of your mother’s sister, for she is your mother’s blood relative” (Lev. 18:13).

The second group of regulations under consideration (Lev. 18:14–16) contains prohibitions against marital relations with the wives of blood relatives. The following regulations belong here:

7) “You shall not uncover the nakedness of your father’s brother; you shall not approach his wife; she is your aunt” (Lev. 18:14). Here there are not two separate regulations, but one, expressed in two forms. The regulation against uncovering the nakedness of one’s father’s brother prohibits precisely what is expressed in the second part of the regulation—namely, “approaching his wife.” Something similar was already noted under point 1.

8) “You shall not uncover the nakedness of your daughter-in-law; she is your son’s wife; you shall not uncover her nakedness” (Lev. 18:15).

9) “You shall not uncover the nakedness of your brother’s wife; it is your brother’s nakedness” (Lev. 18:16).

The third group of regulations (Lev. 18:17–18) contains prohibitions against marital relations with blood relatives of one’s wives.

10) “You shall not uncover the nakedness of a woman and her daughter” (Lev. 18:17); that is, do not marry a mother and her daughter at the same time.

11) “You shall not take the daughter of her son (a granddaughter through a son) or the daughter of her daughter (a granddaughter through a daughter) to uncover her nakedness; they are her blood relatives; it is wickedness” (Lev. 18:17).

12) “You shall not take a woman as a rival to her sister, to uncover her nakedness while the other is alive” (Lev. 18:18). Here it is forbidden to marry two sisters at the same time, because, apart from the moral difficulties, they would through their common husband enter into carnal union with each other, which is impermissible for sisters.

The regulations examined above exhaust the prohibitions of marital relations by degrees of kinship. Looking at this entire circle of prohibitions as a whole, one cannot fail to notice certain gaps in it. Thus, the question inevitably arises: why does the legislator, prohibiting marital relations at the degrees of kinship examined above, remain silent about other degrees of kinship that are nevertheless entirely equal to the first? He says nothing, for example, about marriages with a niece (the daughter of a brother or sister), with the widow of a nephew (the son of a brother or sister), with the widow of a maternal uncle, or with the sister of a deceased wife. Many different opinions have been proposed to resolve these uncertainties and to explain the legislator’s silence. But since the legislator himself provides no guiding thread for their resolution, all of them can only be of a presumptive, probable character. More plausible than the others is the explanation according to which the legislator is silent about marital relations at the indicated degrees in view of their obvious analogy with those degrees of kinship for which the legislator has given precise definitions. Thus, a niece and an uncle stand in the same degree of kinship to each other as a nephew and an aunt. And since marital relations between the latter are prohibited (Lev. 18:14), it follows that the former likewise could not enter into such relations. In general, in such cases one must bear in mind the circumstance that the legislator legally defined only the most important relations; the definition of less important ones he left to customary law, in which, consequently, the indicated uncertainties found their resolution.

Of considerably greater interest to the scholar is the question: what general principles guided the legislator in prohibiting marital relations at the close degrees of kinship indicated above? The resolution of this question is all the more interesting because the Mosaic legislation in this respect presents an almost unique phenomenon in the ancient world, where among some peoples marriage even with a full sister was permitted, so that among the Egyptians, for example, such a marriage was sanctified by the example of Osiris and Isis. Nor does it have historical precedents in ancient Hebrew customary law, in which we find examples of marriage with a half-sister in the case of Abraham (Gen. 20:12), marriage with an aunt in the case of Amram (Exod. 6:20), and marriage with two sisters at the same time in the case of Jacob (Gen. 29:26). If one further takes into account that the Mosaic legislation in this regard had a considerable influence on the more recent European codes, then the importance of the question concerning the reason for the prohibitions examined becomes indisputable.

Scholars hold different views on the reasons for prohibiting marital relations among close degrees of kinship. In the opinion of Michaelis, “the true reason why nations prohibit marriages within close degrees of kinship is to be sought in the fact that without such a prohibition it would be impossible, given the close and constant cohabitation of related persons, to prevent the intrusion of debauchery into family life.” But such a view is not well-founded. If this had been the standpoint of the legislator himself, then, as Ehler justly observes, such marriages would not be shameful in themselves, as the legislator calls them (Lev. 18:17; 20:14 et seq.). If the legislator had had in mind the reason indicated by Michaelis, then, as Saalschütz notes, he would have placed carnal transgression with close female relatives in the same category as a similar crime with strangers, and only in view of the greater likelihood of its occurrence would he have imposed a heavier punishment upon it. Yet the law speaks in a completely different sense. It considers such unions, as stated above, a supreme abomination in themselves, such that the Canaanites are expelled from the land because of them (Lev. 18:24–25), and clearly enough declares that the vileness and criminality consist in the very essence of carnal relations between close relatives. Such a view of the legislator toward the marriages in question gives occasion for another opinion, according to which the prohibitions are grounded in the so-called horror naturalis, or natural aversion, by virtue of which a person instinctively recoils from a marital union with those bound to him by ties of blood and family affection. This basis cannot be denied, for such a feeling genuinely exists, though not firmly enough to serve alone as an explanation for the prohibitions. Indeed, if it fully prevailed, the very strictness of the prohibition would lose its meaning. The most satisfactory explanation is offered by Saalschütz: he locates the basis for the prohibition in the fundamental distinction between familial love and sexual love.

Familial love, he says, in its natural, original purity is a psychological phenomenon in comparison with which sexual love, or marital attraction, is something entirely distinct—more sensual. In the love of parents for children, of children for parents, of brothers and sisters for each other, a particular feeling is expressed, but all these forms of love equally exclude the sensual element just mentioned. Only in the marital union, which for that very reason constitutes the closest bond, do both loves—sexual and familial—merge together, and specifically in such a way that the former, in the pre-marital state (when the young people are in the position of bride and groom), has significance on its own apart from the other, and seeks its satisfaction in the contracting of marriage (we consider it unnecessary to say that by human sexual love is here meant not mere animal sensuality), but with the contracting of marriage, what is properly familial love begins to develop between the spouses, and finally attains predominant significance. Therefore, in the very essence of these human relations lies the fact that sexual love, upon achieving satisfaction, gradually develops out of itself familial love (especially in later life), but that love originally arising from the essence of kinship—that is, love between parents and children, between brothers and sisters—cannot, of itself and psychologically, ever transition into sexual love. If one were thus to attempt to establish in such relationships a connection of both forms of love by means of marriage, they would, instead of merging, rather destroy each other, wherein familial love, developing out of sexual love yet not producing it and therefore excluding it in that respect (hence the love of a father for a son and daughter, the love of a child for mother and father, is indifferently equal), would in an unnatural union not only be wholly paralyzed, but in place of genuinely human sexual love, with its spiritual and moral character, mere animal-sensual inclination would gain predominance. Hence, among those peoples where marital relations with close relatives were permitted (e.g., among the Canaanites, the Egyptians, and others), a complete perversion of natural states and inclinations ensued, whereby both familial and marital love yielded to crude sensuality, by virtue of which a man regarded his mother, daughter, sister, and wife not as a being worthy, by virtue of their very relationship to him, of respect, but as an indifferent means for the satisfaction of his carnal need. How greatly, among those peoples who had shamefully sensual cults (Phalluscultus and others), the carnal gained predominance at the expense of the spiritual is well known, and human dignity demands the recognition that such a state is abnormal, and therefore legislation, whose purpose is to give due significance to the spiritual and moral element, must abolish such a state. But even apart from the unbridled immorality that must generally ensue from the destruction of the natural boundaries between familial and sexual love, these two forms of love are in themselves, in their separate form, so important for the entire structure of civic life that every wise legislator must necessarily turn his first attention to preserving them in their purity and distinctness. Thus, for the sake of producing a morally and physically healthy generation, he must strive to ensure that sexual love does not sink to the level of mere satisfaction of carnal need—without any ideal element of passionate inclination and true, higher love—since the spiritual life of parents is of immense significance for human procreation. On the other hand, the relationship of parents to children, as well as that distinctive feeling which closely binds brothers to sisters and relatives in general to one another—binding them in love, but without the slightest arousal of carnal passions—exerts such a beneficent influence on upbringing, on all the physical, intellectual, and moral formation of rising generations, that the entire civic order, founded precisely on moral principles, would be shaken if the indicated relations were deprived of their natural purity and not kept separate from the relations of an incompatible kind.

The Mosaic legislation, in all its regulations pertaining to the subject under examination, is supremely adapted to keeping both distinct forms of love—sexual and familial—preserved and secured in their natural separateness from each other. The means most certain to lead to this end are as follows. First, the legislator excludes from any possibility of marriage those degrees of kinship at which a person in a natural, uncorrupted state himself recoils from sexual union. He brands marriage at these degrees with strong expressions, calling it an unnatural crime and abomination, a shameful iniquity, a crime against blood kinship, licentiousness, unnatural incest, and threatens it with the most severe punishments. To what degree of membership, in accordance with the principles noted above, close kinship extends—this can be determined only by psychological experience. It is upon such experience that the examined regulations of Moses are based, and they fully retain their significance down to the most recent times. “The prohibitions of marriage within close degrees of kinship,” says one scholar of law, “are given in the Mosaic legislation with such wise definiteness that no subsequent legislation has dared to violate them: they to this day constitute the non plus ultra of canonical freedom.” Second, the legislator limits every sexual inclination exclusively to the form of the marital union (which finds its full justification in the principle of Gen. 2:24). He forbids under threat of the most severe punishments not only every unnatural satisfaction of carnal need, every form of debauchery and enticement, but also establishes a moral law by which one may not covet another man’s wife (Exod. 20:14; Deut. 5:18). Whoever seduces a girl not yet betrothed must marry her. The law utterly does not tolerate public women. Even pagan slave women captured in war were not surrendered by law to the unbridled animal lust of their captors; rather, the latter were required to marry them and bring them into the household as lawful wives. Such regulations—both civil and moral—were to accustom the Jews to suppress in themselves all unlawful inclinations, and consequently to preserve in family relations their natural purity and natural rights. In each regulation concerning the marital union within close degrees of kinship, the legislator expressly makes known that he desires familial relations to be preserved inviolably sacred in their very essence, and therefore designates with precision both their degrees and the offenses against them. As it is said of a wife that she and her husband are one flesh, so too this same view passed over to the relations of kinsmen, and he gave the general prohibition in (Lev. 18:6) its philological expression (scheer basero). Accordingly, marriage with a mother constitutes a double, carnal defilement of the filial relationship—that is, of that familial relationship which is expressed primarily in the form of respectus parentelae — whereby such a marriage is not merely a violation of the duty of reverence toward the mother, but also toward the father (Lev. 18:7). Likewise, a crime is committed against the father if a son uncovers the nakedness of his mother, and so on. The individual provisions set out above are closely bound together by the single concept of blood kinship, and all are clearly directed toward preventing the carnal union of close relatives, because such a union is in itself loathsome and is carnal licentiousness.