Forbidden relationships in Judaism (איסורי ביאה Isurey bi'ah) are intimate relationships which are forbidden by prohibitions in the Torah or rabbinical injunctions.

Some of these prohibitions—those listed in Leviticus 18, known as arayot (Hebrew: עריות)—are considered such a serious transgression of Jewish law that one must give up one's life, rather than transgress one of them.[1] (This does not necessarily apply to a rape victim.[2]) This is as opposed to most other prohibitions, in which one is generally required to transgress the commandment when a life is on the line.

Some of these prohibitions (such as those related to homosexuality), while still observed by Orthodox Jews, are currently observed to a lesser extent or not at all by some of the non-Orthodox movements.


Main article: Thou shalt not commit adultery § In Judaism

Adultery is prohibited by the seventh of the Ten Commandments (Exodus 20:12) which says simply:

Thou shalt not commit adultery.

It is forbidden for a man to have sexual relations with a married woman not his wife. (Leviticus 18:20, 20:10)


Main article: Niddah

A man is not allowed to have sexual relations with a woman—including his wife—during and shortly after her menstrual period (Leviticus 18:19), until after she immerses in a mikveh. A woman who has experienced her menstrual period and has not gone to a proper mikveh is referred to as a niddah.

Religious intermarriage

Main article: Interfaith marriage in Judaism

Religious intermarriage is forbidden in Judaism. There are differing opinions among the rabbis as to when the prohibition on sexual relations with non-Jews is from the Torah, and when it is rabbinic.[3]


Main articles: Jewish views on incest and Incest in the Bible

Biblical prohibitions

Sexual relations with certain close relatives are forbidden in the Hebrew Bible. Though they are generally called incestuous relations, the biblical list does not necessarily correspond to those prohibited under state laws. In the Hebrew Bible, sexual relationships between siblings are forbidden to Jews but permissible to Gentiles (non-Jews).[4]

The relationships forbidden by Leviticus 18 are:

Rabbinically prohibited relationships

In addition to the relationships biblically prohibited to Jews, rabbis have gone further to prohibit additional relationships with various blood relatives or in-laws. These are called "Shni'ot" (secondary prohibitions or seconds). Some of these are:[1]

Adopted children who are raised together are not permitted to marry because of appearances, even if they are not biologically related.[24]

Exclusions from the assembly

The Bible excludes certain categories of people from taking part in the qahal (assembly) of HaShem. Jewish tradition considers this to be solely a limitation on marriage.

Biblical peoples

A Jew is prohibited from marrying a male Moabite and Ammonite convert (Deuteronomy 23:4); or an Egyptian or Edomite convert up to the third generation from conversion (Deuteronomy 23:8–9).

Nethinim/Gibeonites are prohibited by rabbinic injunction.[25]

As the people currently living in those areas may not be descended from the original peoples, these prohibitions may not apply today.[26]


Main article: Mamzer

A mamzer in Jewish law is a child resulting from an incestuous liaison or an adulterous liaison by a married woman.[27] (This is not necessarily the same definition as a bastard by other societies, as it does not include a child of an unmarried woman.)[27] As a mamzer is excluded from the assembly (Deuteronomy 23:3), the Talmud forbids a marriage by an ordinary Jew to a mamzer.[28] However, a mamzer may marry a convert or another mamzer, though their child would also be considered a mamzer.[29]

Certain eunuchs

Jewish tradition also forbids marriage to a man who has been forcibly emasculated; the Greek term spadon (σπάδων; Latin: spado) which is used to refer to such people, is used in the Septuagint to denote certain foreign political officials (resembling the meaning of eunuch).[27] The Jewish prohibition does not include men who were born without visible testicles (conditions including cryptorchidism), or without a visible penis (intersex conditions can affect genital appearance).[27] There is dispute, even in traditional Judaism, about whether this prohibited group of men should include those who have become, at some point since their birth, emasculated as the result of a disease.[30]

Special rules for priests

Israelite priests (kohanim) are not allowed to marry:

Some of these prohibitions are biblical, and some are rabbinical.

The Kohen Gadol (high priest) must also not marry a widow (Leviticus 21:14). He is required to marry a virgin maiden (Leviticus 21:13). However, if he was married to a woman otherwise permitted to a kohen, and was then elevated to the high priesthood, he may remain married to her.

Homosexual acts

Main article: Homosexuality and Judaism

Orthodox view

Orthodox Judaism interprets (Leviticus 18:22) as forbidding homosexual acts between two men, and calls it an abomination. (Leviticus 18:14 specifically prohibits such relationships with one's father or uncle.)[33]

There is no punishment prescribed in the Torah for sex acts between two women (lesbianism), but rabbinic law has prohibited it as an extension of the "activities of (ancient) Egypt" (see Leviticus 18:3).[34] Although the practice is not considered adultery in the formal sense, the Talmud (Yevamot 76a), in the name of Rav Huna, suggests that women engaged in such practices are forbidden to marry a priest of Aaron's lineage. Others posit that such relationships do not prohibit the woman unto a kohen, since it is merely an act of lewdness.[35] However, such practices are still censured and are said to be an infringement of the prohibition, "You shall not do as they do in the land of Egypt" (Leviticus 18:3).[36]

Conservative view

Conservative Judaism's Committee on Jewish Law and Standards has validated different approaches to homosexual acts, with one opinion being like the Orthodox position in many respects, and another opinion permitting many forms of homosexual sex, while continuing to regard anal intercourse between men as prohibited.[citation needed]

According to Conservative rabbi and Bible scholar Jacob Milgrom, the Torah prohibits men lying with men in illicit ways, that are incestuous or adulterous, but otherwise homosexual relations are allowed. [37]

In 2012, the American branch of Conservative Judaism represented by the Rabbinical Assembly, devised a commitment ceremony for same-sex couples, though not defined as kiddushin.[38][39] In 2014, the British group Masorti Judaism said it would support shutafut ceremonies for same-sex unions.[40][41] In 2016, the Rabbinical Assembly passed a resolution supporting transgender rights.[42][43]

Humanistic Judaism

In 2004, the Society for Humanistic Judaism issued a resolution supporting "the legal recognition of marriage and divorce between adults of the same sex", and affirming "the value of marriage between any two committed adults with the sense of obligations, responsibilities, and consequences thereof".[44]

Reform view

Reform Judaism interprets Leviticus 18:22 as forbidding men from using sex as a form of ownership over men. Reform Jewish authors have revisited the Leviticus text, and ask why the text mentions that one should not lie with a man "as with a woman". If it is to be assumed that the Torah does not waste words, the authors ask why the Torah includes this extra clause. Most Reform Jews suggest that since intercourse involved possession (one of the ways in which a man "acquired" a wife was to have intercourse with her), similar to the Christian theology of using sex to "consummate" a marriage, it was abhorrent that a man might acquire another man—it is not the act of homosexual intercourse itself which is abhorrent, but using this act to acquire another man and therefore confuse the gender boundary.[45]


Men and women are forbidden from engaging in bestiality. (Leviticus 18:23) It is considered an abomination according to the Torah.[1]


The Sages taught that 18 is the ideal age to become married, and that before this age one should spend time studying scripture and getting their life in order.[46][47][48][27] The Talmud prohibits for a person to betroth his daughter to a man when she is still a minor, until she is matured and can say "I want to marry so-and-so", because a minor is "incapable of forming an opinion".[49]

However, in Shulchan Aruch it is explained that an exception is added when girls ages 3 through 12 might be given to betrothal by their fathers under distressing situations of exile and persecution, but should be avoided when possible.[50] Nevertheless, it prohibited betrothal by intercourse, with the punishment being rabbinically decreed whiplashes,[51][27] and emphasizes that both betrothal and marriage to minors is forbidden by rabbinic decree.[52] Shulchan Aruch also states that the "deaf-mute", "insane", and "minors" are not fit agents for betrothal "because they are lacking in mental capacity", as such they cannot meaningfully consent.[53][27]

Moreover, The Sages in the Talmud strongly opposed a wide age gap between spouses in either direction (e.g., between a young man and an old woman, and vice versa),[54][55][56] especially in the case of marrying off one's young daughter to an old man, which they declared as reprehensible as forcing her into prostitution.[57] Sanhedrin interpreted that Leviticus 19:29 forbids marrying off one's daughter to an old man because it might lead her to engage in adultery, and the father is fully responsible for causing that situation.[58][57]

The Talmud also teaches that "those who marry minor girls who are not yet capable of bearing children" will "delay the coming of the messiah."[59][60] In Avot de-Rabbi Nathan, Rashbi equates child marriage to murder.[61] Also noteworthy is the teaching of the Talmud and Rambam that if a woman refuses intimacy because she is repulsed by her husband then "her husband should be compelled to divorce her immediately. For she is not like a captive, [to be forced] to engage in relations with one she loathes."[62][63]

See also


  1. ^ a b c Eisenberg 2005, p. 324.
  2. ^ Rama and other commentaries on Shulchan Aruch II:157:1
  3. ^ Shulchan Aruch, III:16:1–2 and commentaries
  4. ^ Kiel, Yishai (2015). "Noahide Law and the Inclusiveness of Sexual Ethics: Between Roman Palestine and Sasanian Babylonia". In Porat, Benjamin (ed.). Jewish Law Annual. Vol. 21. Abingdon, Oxfordshire: Routledge. pp. 64–65. ISBN 978-0-415-74269-6.
  5. ^ "Avodah Zarah 17a:5".
  6. ^ "Yoma 69b:12".
  7. ^ "Mishneh Torah, Negative Mitzvot 353".
  8. ^ "Mishneh Torah, Foreign Worship and Customs of the Nations 10".
  9. ^ "Mishnah Makkot 3:15".
  10. ^ "Sanhedrin 64a:9".
  11. ^ "Ibn Ezra on Leviticus 18:6:3". Retrieved 23 April 2023.
  12. ^ "Sforno on Leviticus 18:6:1". Retrieved 23 April 2023.
  13. ^ "Rabbeinu Bahya, Vayikra 18:6:1".
  14. ^ "Bamidbar Rabbah 20:23".
  15. ^ "Sanhedrin 53b:1".
  16. ^ "Makkot 13b:3".
  17. ^ "Keritot 2b:27". Retrieved 23 April 2023.
  18. ^ "Mishneh Torah, Negative Mitzvot 336".
  19. ^ "Rashi on Deuteronomy 23:1:2".
  20. ^ "Mishnah Yevamot 9:3".
  21. ^ "Mishnah Keritot 3:5".
  22. ^ "Mishneh Torah, Negative Mitzvot 335".
  23. ^ "Talmud Bavli, Gittin 83a, 15".
  24. ^ "The Yichud Prohibition- Part One: To Whom Does It Apply?". 16 November 2002. Archived from the original on 2 July 2013. Retrieved 10 September 2013.
  25. ^ Yevamot 8:2
  26. ^ Mishnah Yadayim 4:4; Rabbi Joseph Karo, Shulchan Aruch, Even HaEzer 4:10 and commentaries
  27. ^ a b c d e f g h Solomon Schechter. "MARRIAGE LAWS –". Retrieved 24 January 2024.
  28. ^ Yebamot, 4:13
  29. ^ Maimonidies, Mishneh Torah, Sanctity, Laws of Sexual Prohibitions, 15:7–8
  30. ^ Jacob ben Asher, Eben ha-'Ezer, 5
  31. ^ Ketubot 22a; Ketubot 27a
  32. ^ Yebamot 24a
  33. ^ Eisenberg 2005, p. 327.
  34. ^ Rabbi Joseph Karo, Shulchan Aruch, Even Ha-'Ezer 20:2
  35. ^ Beit Sh'muel, Shulchan Aruch (Even Ha-'Ezer 20:12, based on Maimonides)
  36. ^ Maimonides, Mishne Torah (Hil. Isurei Bi'ah 21:8)
  37. ^ "Since illicit carnal relations are implied by the term miškĕbê ʾiššâ, it may be plausibly suggested that homosexuality is herewith forbidden for only the equivalent degree of forbidden heterosexual relations, namely, those enumerated in the preceding verses (D. Stewart). However, sexual liaisons occurring with males outside these relations would not be forbidden. And since the same term miškĕbê ʾiššâ is used in the list containing sanctions (20:13), it would mean that sexual liaisons with males, falling outside the control of the paterfamilias, would be neither condemnable nor punishable. Thus miskĕbê ʾiššâ, referring to illicit male—female relations, is applied to illicit male—male relations, and the literal meaning of our verse is: do not have sex with a male with whose widow sex is forbidden. In effect, this means that the homosexual prohibition applies to Ego with father, son, and brother (subsumed in v. 6) and to grandfather—grandson, uncle—nephew, and stepfather—stepson, but not to any other male." - Jacob Milgrom, Leviticus 17-22: A New Translation With Introduction and Commentary, Anchor Yale Bible vol. 3, Yale University Press, 2007, page 1569
  38. ^ Sales, Ben (4 June 2012). "Conservative rabbinic group issues guidelines for same-sex wedding rituals". Jewish Telegraphic Agency. Retrieved 26 November 2021.
  39. ^ "US Conservative Jews approve gay weddings". Ynet. The Associated Press. 2 June 2012. Retrieved 26 November 2021.
  40. ^ Hoare, Liam (1 May 2015). "British Rabbis Play Matchmaker for LGBTQ Jews". Slate. Retrieved 26 November 2021.
  41. ^ "Masorti Judaism says yes to same-sex ceremonies". Masorti Judaism (UK). 22 October 2014. Retrieved 26 November 2021.
  42. ^ "The rabbis of Conservative Judaism pass a resolution supporting transgender rights". Washington Post. ISSN 0190-8286. Retrieved 26 November 2021.
  43. ^ "Resolution Affirming the Rights of Transgender and Gender Non-Conforming People". Rabbinical Assembly. 6 April 2016. Retrieved 26 November 2021.
  44. ^ "Society for Humanistic Judaism Supports Marriage Rights of Same-Sex Couples". April 2004. Archived from the original on 10 October 2013. Retrieved 19 November 2013.
  45. ^ "homosexuality | contemporary-issues | a-to-z-of-reform-judaism- The Movement for Reform Judaism". Archived from the original on 3 April 2013. Retrieved 10 September 2013.
  46. ^ "The Age of Marriage for Men – Peninei Halakha". Retrieved 24 January 2024.
  47. ^ "Sotah 44a.6 –". Retrieved 24 January 2024.
  48. ^ "Pirkei Avot 5.21 –". Retrieved 24 January 2024.
  49. ^ "Kiddushin 41a.8 –". Retrieved 24 January 2024.
  50. ^ "Shulchan Aruch, Even HaEzer 37:8 –". Retrieved 24 January 2024.
  51. ^ "Shulchan Aruch, Even HaEzer 26:4 –". Retrieved 24 January 2024.
  52. ^ "Shulchan Aruch, Even HaEzer 43.1-2 –". Retrieved 24 January 2024.
  53. ^ "Shulchan Aruch, Even HaEzer 35.6 –". Retrieved 24 January 2024.
  54. ^ "Yevamot 44a –". Retrieved 24 January 2024.
  55. ^ "Yevamot 101b –". Retrieved 24 January 2024.
  56. ^ "Avot D'Rabbi Natan 23:4 –". Retrieved 24 January 2024.
  57. ^ a b "Sanhedrin 76a 23-25 –". Retrieved 24 January 2024.
  58. ^ "Sanhedrin 76b 2 –". Retrieved 24 January 2024.
  59. ^ "Niddah 13b.5-7 –". Retrieved 24 January 2024.
  60. ^ "The Age of Marriage for Women – Peninei Halakha". Retrieved 25 January 2024.
  61. ^ Avot de-Rabbi Natan, Version B, 48:66
  62. ^ "Ishut 14:8 –". Retrieved 24 January 2024.
  63. ^ "Ketubot 63b.7-8 –". Retrieved 24 January 2024.

Further reading