“ ‘You shall not take a wife in addition to her sister, to be a rival, to uncover her nakedness, while her sister is still alive.
Not to have sexual relations with one's wife's sister during one's wife's lifetime
The cited verse
The Hebrew (Masoretic Text)
וְאִשָּׁה אֶל־אֲחֹתָהּ לֹא תִקָּח לִצְרֹר לְגַלּוֹת עֶרְוָתָהּ עָלֶיהָ בְּחַיֶּיהָ
In Maimonides’ words
How Maimonides defines this commandment in his Sefer HaMitzvot — his own words, shown as a primary source.
הזהירנו מגלות ערות אחות אשתו בחיי אשתו. והוא אמרו ואשה אל אחותה לא תקח. והעובר על לאו זה בכרת אם הוא מזיד ובשוגג יקריב קרבן חטאת קבועה:
He prohibited us from sexual intercourse with the sister of his wife during the lifetime of his wife. And that is His, may He be blessed, saying, "You shall not take a woman and her sister" (Leviticus 18:18). And one who transgresses this negative commandment is [punished] by excision if it was volitional. But [if] inadvertent, he must sacrifice a fixed sin-offering.
Hebrew: Sefer HaMitzvot, Warsaw 1883 (public domain). English: Sefaria Edition, trans. Rabbi Francis Nataf, 2021 (CC0). Via Sefaria; translator’s footnotes omitted.
Literary form: a prohibition
Applicability
How the catalog describes where and when this commandment applies. These are independent descriptions, not a verdict on which laws still count.
- Recorded as practiced today
Classical halakhic consequences
The consequences the classical halakhah attaches to this commandment, grouped by who imposes them. Where a category has none recorded, that absence is itself meaningful.
Imposed by a court
- Lashes (malkot)
At the hands of Heaven
- Karet — being 'cut off'
Ritual remedy
- A sin-offering (ḥatat)
How the streams of Judaism treat this commandment
The streams of Judaism read the same commandment differently — an ongoing plurality, not a ranking. Each position below is reported as the catalog records it; none is presented as the correct one.
- Orthodox Binding
- Conservative Binding
- Reform As the catalog records it: affirmed non halakhic
- Reconstructionist As the catalog records it: affirmed non halakhic
- Karaite As the catalog records it: binding extended to general polygamy
24 of 613 commandments have been examined in depth so far — this one is queued.
How later traditions received this commandment
How later traditions read or reworked this commandment, each attributed to its own voice. The catalog’s own classification of each reception is shown as it records it, never adopted as GEBible’s.
Qumran (the Dead Sea Scrolls)
- CD 4:20-5:2 The catalog describes this reception as: extended to general polygamy
Philo of Alexandria
- De Specialibus Legibus 3.26-28 rationalized it
The Qur'an and hadith
- Q 4:23 carried a parallel
Beside the older legal codes of its world
The commandment set beside the ancient Near-Eastern legal collections scholars compare it to — a descriptive comparison, not a claim of dependence.
- hittite laws regulation of permitted and prohibited sexual unions, including unions involving sisters and related women Relationship to the parallel: parallel with divergence §§191-194 Roth, Law Collections from Mesopotamia and Asia Minor, 2nd ed. (1997)
- code of hammurabi regulation of the naditu-priestess who provides a slave-woman (shugitu) to her husband to bear children, with provisions governing the resulting co-wife status and friction; thematically related to (though not identical with) the surrogate co-wife dynamics of Genesis 29-30 Relationship to the parallel: shared theme §§144-147 Roth, Law Collections from Mesopotamia and Asia Minor, 2nd ed. (Scholars Press, 1997)
Where this commandment meets modern human-rights frameworks
One modern normative lens, attributed to it — not GEBible’s assessment. Each row names the framework it measures against and the catalog’s own classification of the relation.
This framework catalogues tensions; it records agreement in only one of its entries. The near-total tension rate is the shape of the instrument, not a finding.
No tension with the catalogued modern frameworks is recorded here.