INCEST AND INBREEDING. Incest and inbreeding are two different but related aspects of marriage and human reproduction: the former a legal and culturally determined concept that regards specific cases of sexual relationship, the latter a biological notion that concerns processes and tendencies in the reproduction of a population. Next-of-kin marriage in pre-Islamic Persia cannot be called incest by the standards of Zoroastrianism, since incest implies forbidden relationships (see FAMILY LAW i.). The coming of Islam changed this, by making Arab customs the basis of Islamic family law.

Among the pre-Islamic Arabs, as today, marriage with parallel cousins (with father’s brother’s daughter) was the preferred union; anything closer was deemed improper. The few cases of reported next-of-kin-marriages, or sexual encounters, in pre-Islamic Arabia are explained in the sources as the result either of alcohol abuse or of influence of Sasanian Zoroastrianism. The favored union, therefore, was and is the one that is closest to the forbidden categories. There are various reports that show that the Bedouins were aware of the dangers of protracted in-marrying in this manner and the resulting inbreeding. An often-quoted saying, either anonymous or attributed to the caliph ʿOmar b. al-Ḵaṭṭāb or to the Prophet, is “Take strangers; then you will not produce stunted offspring!” Jāḥeẓ (d. 255/869) reports the words of an Arab who paradoxically boasts of his scrawny physique as a sign of noble (in)breeding (Jāḥeẓ, Borṣān, pp. 15-16).

The Koran provides the basic rules on marriage impediments based on consanguinity, affinity, and fosterage (4:22-23). A man may not marry his mother, daughter, sister, aunt, niece, foster-mother, foster-sister, mother-in-law, stepmother (or any of his father’s wives), stepdaughter, or daughter-in-law, or be married to two sisters at the same time. Such a non-marriageable person is called maḥram (plur. maḥārem) or ḏāt maḥram, a word derived from the well-known Arabic root ḤRM, implying being taboo, inviolable, or sacrosanct. There is no specific term for incest in Arabic or Persian. Legal scholars and exegetes have more precisely defined these categories. Thus the words “mother” and “daughter,” for instance, were understandably taken to imply grandmothers and granddaughters, or any female ascendant or descendant; similarly “aunt” includes all sisters and aunts of ascendants. Furthermore, a man may not marry two women who are related in such a way that, if one were a man, they would not be allowed to marry. The theologians took pains to show that these rules were more or less natural to the Arabs; the only differences were that (1) in pre-Islamic Arabia marriage with one’s father’s wife was not uncommon (in the Koranic text this union is singled out with especially strong condemnation as “indecent and hateful, an evil way”), and (2) it happened that a man was married to two sisters simultaneously. The main novelty of the Koranic rules is the inclusion of milk-relationship (rażāʿ) among the marriage impediments: a wetnurse becomes like a mother. Legal scholars have posited that a milk-relationship establishes exactly, or nearly exactly, the same impediments as blood relationship, so that one may not marry, for instance, the sister of one’s foster-mother or a girl suckled by one’s own mother or wetnurse. Various explanations, some of them ingenious, have been proposed for this unique rule. Whatever its origin, it is of considerable practical importance.

Islamic manuals of positive law discuss the marriage impediments in great detail in two contexts, in the sections on marriage (nekāḥ) and on punishments (ḥodud). As always, the jurists display great ingenuity to make the system as complete and as consistent as possible, dealing with every imaginable (and often hypothetical) difficulty. They are only rarely interested in the rationale behind the rules. Some authors, however, who combine legal and ethical interests, attempt to provide a justification of the rules. Thus an appeal is made to man’s “sound natural disposition,” which makes him abhor incest; Islamic law merely makes this disposition explicit. Others reject this and maintain that God’s inscrutable wisdom and commands in this matter cannot be explained rationally. Yet others prefer a social and ethical explanation: marrying next-of-kin would cause all kinds of strife and jealousy within the family, or would impose humiliation on female relatives that ought to be respected and honored. This view sees the sexual act as involving some kind of aggression and humiliation.

In the sections on legal punishments, incest is dealt with as a case of fornication (zenā). It is generally felt that it is an especially grave form of zenā if it is committed knowingly, and many authorities (including many Hanbalite and most Shiʿite scholars) argue that it should be punished with death. Legal proof of fornication is, in any case, difficult in Islam, and one finds very few well-attested cases in the sources; after all, incest is, perhaps more than other forms of fornication, often covered up and kept, literally, within the family. Fatwā collections, which often reflect real-life concerns better than prescriptive manuals, seem to indicate that people were preoccupied with problems relating to milk-relationship rather than with other forms of incest. Interesting discussions have been held regarding marriage with one’s daughter born out of wedlock, from an adulterous union; according to Šāfeʿi, this is possible, since the girl is not legally the man’s daughter, in view of the well-known legal maxim that a child “belongs to the marriage bed.” Not surprisingly, some lively polemics resulted from this opinion. Another complication is that according to many scholars impediments may result not only from complete sexual congress but also from any “lustful” touch or even gaze; thus any woman, “lustfully” touched by a man would be forbidden to his son, in theory at least.

Marriage rules help to define a religion and a culture; the alleged practices of the Zoroastrians are a recurrent motif in Muslim texts and are used to distinguish between “us” and “them.” Heretical sects are often credited with a sexual free-for-all or holding women as communal sex objects, with all the implications of possible incest. The Arabs, who knew about the Zoroastrian next-of-kin unions in pre-Islamic times, frequently taunt Persians with this custom, even though it is likely that even in Sasanian times it was never widely practised, and there is no clear proof that it survived in Islamic times. It has been maintained that the extreme forms of next-of-kin marriages persisted until the tenth century, after which it survived only as the marriage of first cousins, wholly compatible with Islamic law and customs (Boyce, Zoroastrians, p. 54). According to Spuler (pp. 377-78) the stamping out of close-kin marriage in Iran during the ninth and tenth centuries was a difficult process, but the evidence he gives is meager, limited to two not very convincing reports. Other “evidence” to be disregarded is found in lampoons, which, obviously, should not be taken at face value. Reports on sectarians who are accused of propagating and practicing sexually deviant customs, among them marriages that are incestuous by Islamic standards, should also be treated with caution, and one should not jump to conclusions by positing the existence of Zoroastrian vestiges; see, e.g., the reports on Ḥamza b. ʿOmāra, a Shiʿite, of whom it has been said that he followed Persian customs (Watt, p. 46). The Arabic poet and prose writer, Abu’l-ʿAlāʾ Maʿarri (d. 449/1058), accusing a heretical Islamic sect, the Carmathians, of incestuous practices, contrasts them with the Zoroastrians, who allegedly had given up their habits:

Even the brute beasts did not approve the crimescommitted by you on your mothers and mothers-in-law.

We questioned some Magians as to the real nature of their religion.

They replied, “Yes: we do not wed our sisters.

That, indeed, was originally permitted in Magianism, but we count it an error.

We reject abominable things …” (tr. Nicholson, p. 104; Arabic text, ibid., p. 239)

Among the sects that are said to have allowed marriage with granddaughters and great-nieces are the ʿAjāreda (followers of Ebn ʿAjarrad) and the Maymuniya, followers of a certain Maymun (Ašʿari, I, p. 95). These two groups are classified among the politico-religious movement of the Kharijites and were active in 2nd/8th-century Khorasan. Maymun’s views are said, by medieval and modern scholars, to have been adopted from the Zoroastrians. However, it is also possible that they are simply the result of a very literalist reading of the Koranic text (which does not mention granddaughters), rather than vestiges of Zoroastrianism.

Doctrinally the opposite of the Kharijites, some extreme Shiʿites (the various Ismaʿili sects and movements) have also been accused of adopting Zoroastrian marriage customs. The Bāṭeniya (or Ismaʿilis; see Ismaʿilism) are charged with allowing “marriage with daughters and sisters, drinking wine, and all sorts of sensual pleasures” (Baḡdādi, p. 270). Behāfarid b. Farvardin, who led an uprising near Nišāpur around 129/747 (soon crushed by Abu Moslem [q.v.], the organizer of the Abbasid revolution), and who acted as a kind of Neo-Zoroastrian prophet, spoke out against the practice; this does not prove that the practice was still common in his time.

The lack of contemporary evidence did not stop theoretical legal discussions or polemics. Against scholars who wanted to prohibit next-of-kin marriage among the Zoroastrians, it was argued that since they, as a “protected” community, were allowed to persist in unbelief, surely a greater sin than next-of-kin marriage, the latter should be tolerated too. Abu Ḥayyān Tawḥidi (who may have been a Persian himself), in his Arabic al-Emtāʿ wa’l-moʾānasa, records a conversation he had around 375/985 with a Buyid vizier on the superiority of the Arabs over the Persians. In a lengthy quotation ascribed to the Qāżi Abu Ḥāmed Marvaruzi (d. 362/973), himself a Persian, the latter takes the side of the Arabs and argues that the Persians, deceived by Zoroaster and induced by him to marry their mothers, sisters, and daughters, are inferior to the Arabs, who, even when still uncouth Bedouins untaught by religion or civilization, by their nature abhorred such practices (Tawḥidi, I, pp. 90-95).

A Persian prince, Marzobān b. Rostam b. Šarvin of Perim (second half of 4th/10th century), maintained that it had all been a misunderstanding. Zoroaster had not commanded his followers to copulate with their mothers. He had been asked by the leading scholars of his time what someone should do who, isolated from others, was left with his own mother; should he (by analogy with Lot and his daughters) ensure the survival of his line by bedding the only woman available? Zoroaster had ruled that it was allowed, and his fatwā was misinterpreted (Fück, p. 75).

Incest serves as literary and narrative motif in myths, legends, and stories, such as creation stories (the children of Adam and Eve, or those of Gayōmart [q.v.] in Zoroastrian lore), the legend of Loqmān (who was deceived into sleeping with his sister), or popular stories and epics (involving, for instance, wicked fathers who have designs on their daughters, or sinning siblings who love each other passionately). Compared with the great proliferation of the motif in Western literatures, Arabic literature has little to offer, and it would seem that medieval Persian authors are even more reticent, which could mean either that the taboo on discussing it (other than in legal contexts) is as great as the taboo on the act itself, or that incest is a more marginal phenomenon in Middle Eastern culture than it is in the West. Stories involving incest (by Islamic standards) in Persian are usually projected into the pre-Islamic past, such as the case of King Bahman (father of Sāsān) and his daughter Homāy.

In one of the Persian courtly romances next-of-kin unions are prominent: Vis o Rāmin, written soon after 441/1050 by Faḵr al-Din Gorgāni (q.v.). Vis, a princess, is married to her full brother Viru by her mother, who argues that no other husband is worthy of her. The girl is willing, but the marriage is not consummated. In fact the girl has been promised by her mother to king Mōbad (whose name means “Zoroastrian priest”) and she is duly married to him, this marriage remaining unconsummated, too. In the end, Vis, widowed, is united with her lover Rāmin, Mōbad’s brother. Rāmin, however, is Vis’s milk-brother, so the story is utterly un-Islamic in its marital arrangements. No time is mentioned, but it is obviously presented as a pre-Islamic tale; its origin may have to be sought in the time of the Parthian Arsacid dynasty. Gorgāni tells the story without any comment, neither justifying the marriages historically nor condemning them as a good Muslim. Kappler, however, sees the matter as central in the story. If it contains immorality, from a Zoroastrian point of view, the main culprit is old king Mōbad, who breaks up a marriage of brother and sister, a great sin according the old Pahlavi texts. In the end, the just cause triumphs, since the girl marries her milk-brother, who therefore is in fact her brother. Kappler mentions another interpretation, which reads the romance as the successful attempt of a girl to escape from in-marrying to out-marrying, the nurse being the link between the two domains of family and strangers.



Ašʿari, Maqālāt al-islāmiyin, ed. Helmut Ritter, Istanbul, 1929-30.

ʿAbd-al-Qāher Baḡdādi, al-Farq bayn al-feraq, ed. Moḥammad Badr, Cairo, 1910.

Laleh Bakhtiar, Encyclopedia of Islamic Law: A Compendium of the Major Schools, Chicago, 1996, pp. 408-23.

Mohammed Hocine Benkheira, “Donner le sein, c’est comme donner le jour: la doctrine de l’allaitement dans le sunnisme médiéval,” Studia Islamica 92, 2001, pp. 5-52.

Pierre Bonte, ed., Épouser au plus proche: Incest, prohibitions et stratégies matrimoniales autour de la Méditerranée, Paris, 1994.

Mary Boyce, Zoroastrianism: Its Antiquity and Constant Vigour, Costa Mesa, 1992.

Johann Fück, “Sechs Ergänzungen zu Sachau’s Ausgabe von al-Bīrūnīs Chronologie orientalischer Völker,” in J. Fück, ed., Documenta Islamica Inedita, Berlin, 1952, pp. 69-98.

Faḵr-al-Din Gurgāni, Vis and Ramin, tr. from the Persian by George Morrison, New York, 1972.

Françoise Héritier, Two Sisters and Their Mother: The Anthropology of Incest, tr. Jeanine Herman, New York, 2002 (originally published as Les Deux soeurs et leur mère: Anthropologie de l’incest, Paris, 1994).

Jāḥeẓ, al-Borṣān wa-l-ʿorjān, ed. Moḥammad Morsi al-Ḵawli, Beirut, 1981.

Claude-Claire Kappler, “Vîs et Râmîn, ou comment aimer un autre que son frère … ?” Luqmān 7/2, 1991, pp. 55-80.

Reynold Alleyne Nicholson, Studies in Islamic Poetry, Cambridge, 1921.

Bertold Spuler, Iran in frühislamischer Zeit, Wiesbaden, 1952.

Abu Ḥayyān Tawḥidi, al-Emtāʿ wa-l-moʾānasa, ed. Aḥmad Amin and Aḥmad al-Zayn, Cairo, 1939-53.

Geert Jan van Gelder, Close Relationships: Incest and Inbreeding in Classical Arabic Literature, in preparation. William Montgomery Watt, The Formative Period of Islamic Thought, Edinburgh, 1973.

(Geert Jan Van Gelder)

Originally Published: December 15, 2004

Last Updated: March 27, 2012

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Vol. XIII, Fasc. 1, pp. 5-6