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SBL e-journal

Isaac S. D. Sassoon





The Biblical Prohibition of Polygyny?



APA e-journal

Isaac S. D. Sassoon





The Biblical Prohibition of Polygyny?






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The Biblical Prohibition of Polygyny?

Popular legend tells us that Rabbenu Gershom (d. ca 1028) was the first to prohibit polygyny. The Damascus Covenant’s understanding of the law in Leviticus 18:18, however, suggests that polygyny may have been prohibited more than a thousand years earlier by the Priestly authors.


The Biblical Prohibition of Polygyny?

Elkanah with his Two Wives, Ninth German Bible (Cologne Bible) (Anton Koberger: Nurenburg: 1483) Los Angeles County Museum of Art

The ostensible source for the law prohibiting a man from marrying two sisters is Leviticus 18:18:

ויקרא יח:יח וְאִשָּׁ֥ה אֶל־אֲחֹתָ֖הּ לֹ֣א תִקָּ֑ח לִצְרֹ֗ר לְגַלּ֧וֹת עֶרְוָתָ֛הּ עָלֶ֖יהָ בְּחַיֶּֽיהָ:
Lev 18:18 Do not marry a woman as a rival (lizror) to her sister (el achotah) and uncover her nakedness in the other’s lifetime.[1]

The LXX already understands this verse, as prohibiting marrying two sisters: “You shall not take a wife in addition to her sister as a rival to uncover her nakedness in opposition to her while she is yet living.” But this understanding is not at all obvious or certain.


The first three words of the verse, constitute a formidable crux. Literally, of course, isha means woman (or wife) and ahot means sister. Hence the usual translations. However, the phrase ishah el ahotah is another matter. It occurs eight more times in Scripture:

Exod 26:3 (x2)

חֲמֵ֣שׁ הַיְרִיעֹ֗ת תִּֽהְיֶ֙יןָ֙ חֹֽבְרֹ֔ת אִשָּׁ֖ה אֶל־אֲחֹתָ֑הּ וְחָמֵ֤שׁ יְרִיעֹת֙ חֹֽבְרֹ֔ת אִשָּׁ֖ה אֶל־אֲחֹתָֽהּ:
Five of the cloths shall be joined to one another, and the other five cloths shall bejoined to one another.

Exod 26:5

מַקְבִּילֹת֙ הַלֻּ֣לָאֹ֔ת אִשָּׁ֖ה אֶל־אֲחֹתָֽהּ:
The loops to be opposite one another.

Exod 26:6

וְחִבַּרְתָּ֙ אֶת־הַיְרִיעֹ֜ת אִשָּׁ֤ה אֶל־אֲחֹתָהּ֙ בַּקְּרָסִ֔ים
And couple the cloths to one another with the clasps.

Exod 26:17

שְׁתֵּ֣י יָד֗וֹת לַקֶּ֙רֶשׁ֙ הָאֶחָ֔ד מְשֻׁלָּבֹ֔ת אִשָּׁ֖ה אֶל־אֲחֹתָ֑הּ
Each plank shall have two tenons, parallel to each other.

Ezek 1:9

חֹֽבְרֹ֛ת אִשָּׁ֥ה אֶל־אֲחוֹתָ֖הּ כַּנְפֵיהֶ֑ם
Each one’s wings touched those of the other.

Ezek 1:23

וְתַ֙חַת֙ הָרָקִ֔יעַ כַּנְפֵיהֶ֣ם יְשָׁר֔וֹת אִשָּׁ֖ה אֶל־אֲחוֹתָ֑הּ
Under the vault their wings were spread straight toward those of the others.

Ezek 3:13

וְק֣וֹל׀ כַּנְפֵ֣י הַחַיּ֗וֹת מַשִּׁיקוֹת֙ אִשָּׁ֣ה אֶל־אֲחוֹתָ֔הּ
With the sound of the wings of the creatures beating against one another.

All eight examples come from Priestly or Priestly style (=Ezekiel) texts, as does Lev 18:18. In all eight instances the phrase is being used idiomatically to signify a relationship of symmetry or congruity between two objects or sets of objects; in no case does the ishah or the ahot refer to a person. In addition, it is unlikely that Hebrew would use the preposition ’el rather than the conjunction vav to express marrying a woman and her sister.

Rivals (צ-ר-ר)

The term litzror in the verse’s second half is another crux. It typically means “to bind, constrict,” but can also denote the idea of “to cause rivalry,” as reflected in צ-ר-ר’s derivative noun צרה (pl. צרות). Like its Akkadian cognate ṣerretu,[2] צרה may refer to a “rival,” particularly a rival wife.[3]

For example, Channah and Penina (who are not depicted as sisters) are described as rivals (צרות):

שמואל א א:ו וְכִֽעֲסַ֤תָּה צָֽרָתָהּ֙ גַּם־כַּ֔עַס בַּעֲב֖וּר הַרְּעִמָ֑הּ כִּֽי־סָגַ֥ר יְ-הֹוָ֖ה בְּעַ֥ד רַחְמָֽהּ:
1 Sam 1:6 Moreover, her (Channah’s) rival (Peninah), to make her miserable, would taunt her that Yhwh had closed her womb.

Now if the phrase “a woman and her sister” is to be understood as literally denoting sisters, then litzror would seem otiose. Presumably, a prohibition of marrying sisters would be due to it being considered a form of incest, not to the fear that sisters would be rivals. As shown by the case of Channah, a second wife can always be a “rival” to the first (and vice versa), sisters or not.

In Her Lifetime

The verse’s be-hayehah proviso is also problematic, being unparalleled throughout Levitcus’ incest laws. Its singularity stands out sharpest when juxtaposed with a parallel proscription in Lev 18:16, which prohibits a union between a man and his brother’s wife.

עֶרְוַ֥ת אֵֽשֶׁת־אָחִ֖יךָ לֹ֣א תְגַלֵּ֑ה עֶרְוַ֥ת אָחִ֖יךָ הִֽוא:
Do not uncover the nakedness of your brother’s wife; it is the nakedness of your brother.

The verse does not add בחייו, “in his lifetime,” and the prohibition does not appear to lapse at the brother’s death. So if a woman is barred from marrying her husband’s brother even after her husband’s death, why should a man be at liberty to marry his wife’s sister after his wife’s death?

Prohibition Against Polygyny

What if instead of proscribing marriage between a man and two sisters, Lev 18:18 were reflecting the Priestly Torah’s wish to abolish polygyny – i.e., a man marrying more than one wife?[4]

The Yibbum Problem

An objection often raised against such a reading of the verse is the mitzvah of levirate marriage (yibbum) in Deut 25:5-10. If polygyny is forbidden, then a married man would not be able to marry his deceased brother’s widow; and yet according to the laws of yibbum he would have to. This is a serious argument for those who see the Torah as a homogenous document. But for source critics, it cannot be taken for granted that P endorses laws belonging to other law-codes. Hence, P need not have subscribed to Deuteronomy’s institution of yibbum.[5]

Precedent of Anti-Polygyny Interpretation: The Damascus Covenant (CD)

This interpretation of the verse has a long pedigree. The Dead Sea Scroll known as the Damascus Covenant (hereafter CD) clearly understood Lev 18:18 in this way:

בוני החיץ… הם ניתפשים בשתים בזנות לקחת שתי נשים בחייהם ויסוד הבריאה זכר ונקבה ברא אותם ובאי התבה שנים שנים באו אל התבה, ועל הנשיא כתוב לא ירבה לו נשים.
The builders of the partition (bonei ha-hayis)… they are caught twice in fornication by taking two wives in their lifetimes; also the principle of creation is (Gen 1:27) male and female He created them. And the ones who went into the ark “went two by two into the ark” (Gen 7:9) And regarding the prince (=king) it is written (Deut 17:17) he shall not multiply wives to himself…” (CD 4:19-5:2).

From references to a group thus named elsewhere in the scrolls, scholars have concluded that “Builders of the partition” is a code name for the Pharisees, who are known to have permitted and possibly practiced polygyny. Since the Pharisees interpret Lev 18:18 as a prohibition against marrying two biological sisters, this leaves open the possibility of marrying two women who are not sisters. CD is polemicizing against that tradition of the “Builders,” with a not so subtle paraphrase of Lev 18:18 “taking two wives in their lifetimes.”

CD 4:20-21 Lev 18:18
לקחת שתי נשים בחייהם וְאִשָּׁ֥ה אֶל־אֲחֹתָ֖הּ לֹ֣א תִקָּ֑חבְּחַיֶּֽיהָ

By taking two wives in their lifetimes.

Do not take a wife when it is during another wife’s… lifetime.

CD doubles the biblical prohibition by claiming that polygyny violates the rights of both women, not just the first wife.

Popular legend tells us that Rabbenu Gershom (d. ca 1028) was the first to prohibit polygyny. Although the historicity of this ascription has been disputed,[6] the custom took root in medieval Ashkenaz and became standard practice in the Ashkenazi Jewish community by the 12th century.[7] This Ashkenazi ban, however, did not claim Talmudic—and certainly not scriptural—authority as CD did.[8]

On the other hand, unlike Cherem de-Rabbeinu Gershom, CD’s reading of the verse did not prevail. (It was very likely bullied into silence and into long oblivion!)


May 3, 2016


Last Updated

October 16, 2021


View Footnotes

Dr. Hacham Isaac S. D. Sassoon is a rabbi and educator and a founding member of the ITJ. He studied under his father, Rabbi Solomon Sassoon, Hacham Yosef Doury, Gateshead Yeshivah and received his semicha from the Chief Rabbinate of Israel. He holds a Ph.D. in literature from the University of Lisbon. He is the author of The Status of Women in Jewish Tradition (Cambridge University Press 2011), a commentary on chumash called Destination Torah (Ktav 2001), and most recently the co-editor with Rabbi Steven H. Golden of the Siddur 'Alats Libbi (Ktav 2020).