עֶרְוַת אִשָּׁה וּבִתָּהּ לֹא תְגַלֵּה – שֶׁלֹּא לְגַלּוֹת עֶרְוַת אִשָּׁה וּבִתָּהּ, שֶׁנֶּאֱמַר (ויקרא יח יז) עֶרְוַת אִשָּׁה וּבִתָּהּ לֹא תְגַלֵּה. וּבָא הַפֵּרוּשׁ שֶׁאֵין הַחִיּוּב אֶלָּא כְּגוֹן שֶׁנָּשָׂא הָאַחַת תְּחִלָּה, וְאַחַר כָּךְ כְּשֶׁבָּא עַל הַשְּׁנִיָּה הוּא מִתְחַיֵּב, אֲבָל אִם לֹא נָשָׂא אַחַת מֵהֶן לֹא יִתְחַיֵּב עֲלֵיהֶן, לְפִי שֶׁכָּתוּב בָּהֶן לְשׁוֹן אִישׁוּת וְקִיחָה, דְּמַשְׁמַע עַל יְדֵי נִשּׂוּאִין דְּהָכִי מַשְׁמַע לָן לְשׁוֹן קִיחָה בְּכָל מָקוֹם לְשׁוֹן נִשּׂוּאִין אֲבָל חֲכָמִים גָּזְרוּ גָּדֵר וְאָמְרוּ, שֶׁאִם נֹאֵף אָדָם עִם אִשָּׁה אָסוּר לִשָּׂא בִּתָּהּ כָּל הַשֶּׁבַע נָשִׁים קְרוֹבוֹתֶיהָ כָּל זְמַן שֶׁהַזּוֹנָה קַיֶּמֶת, מִפְּנֵי שֶׁהַזּוֹנָה בָּאָה לְבַקֵּר אוֹתָן וְלִבּוֹ גַּס בָּהּ וְשֶׁמָּא יָבוֹא לִידֵי עֲבֵרָה. The nakedness of a woman and her daughter, you shall not reveal: To not reveal the nakedness of a woman and her daughter, as it is stated (Leviticus 18:17), “The nakedness of a woman and her daughter, you shall not reveal.” And the explanation came that the liability is only in such a case that he married one first; and then when he had intercourse with the second, he becomes liable. But if he did not marry one of them, he does not become liable for them. [This is] since an expression of marriage is written about them — “taking,” which implies through marriage. As so is it understood to us, that the expression of taking is an expression of marriage in every place. But the Sages decreed a fence and said that if a man has adultery with a woman, it is forbidden to marry her daughter — [even] all of her seven [delineated] relatives — so long as the unfaithful woman is alive. [This is] because the unfaithful woman comes to visit them and [so] he will isolate himself with her; and [since] he is familiar with her, he will perhaps come to a sin.
וְנוֹהֵג אִסּוּר זֶה בְּכָל מָקוֹם וּבְכָל זְמַן. וְהָעוֹבֵר עָלֶיהָ וְשָׁכַב אֶת אִשָּׁה וְאֶת בִּתָּהּ שְׁנֵיהֶם נִשְׂרָפִין, הוּא וְאוֹתָהּ שֶׁשָּׁכַב אַחֲרוֹנָה, שֶׁאֵין לָרִאשׁוֹנָה חֵטְא שֶׁהֲרֵי בְּהֶתֵּר נְשָׂאָהּ, וְאִם בָּא עַל הַשְּׁנִיָּה אַחַר מִיתַת אִשְׁתּוֹ הָרִאשׁוֹנָה הֲרֵי אֵלּוּ בְּכָרֵת, וְאֵין בָּהֶן מִיתַת בֵּית דִּין, שֶׁנֶּאֱמַר בְּמָקוֹם אַחֵר בְּסֵדֶר קְדוֹשִׁים תִּהְיוּ (כ יד) בָּאֵשׁ יִשְׂרְפוּ אֹתוֹ וְאֶתְהֶן. וּפֵרֵשׁ רַבִּי אֱלִיעֶזֶר בְּסַנְהֶדְרִין (סו, ב) בָּאֵשׁ יִשְׂרְפוּ אוֹתוֹ וְאַחַת מֵהֶן, דְּהַיְנוּ הָאַחֲרוֹנָה, כְּמוֹ שֶׁאָמַרְנוּ. וְדַוְקָא כְּשֶׁשְּׁתֵּיהֶן קַיָּמוֹת שֶׁכֵּן בָּא הַפֵּרוּשׁ אֲבָל כְּשֶׁאֵין שְׁתֵּיהֶן קַיָּמוֹת אֵין שָׁם שְׂרֵפָה, אֶלָּא שֶׁהֵן בְּחִיּוּב כָּרֵת בְּמֵזִיד, וּבְשׁוֹגֵג מֵבִיא חַטָּאת קְבוּעָה. וְרַבִּי עֲקִיבָא מְפָרֵשׁ שָׁם, אוֹתוֹ וּשְׁתֵּיהֶן, וּכְגוֹן שֶׁנָּשָׂא הַשְּׁתַּיִם בְּאִסּוּר, וְיִמָּצֵא זֶה כְּשֶׁנָּשָׂא הַבַּת וְאִמָּהּ וְאֵם אִמָּהּ. וְשָׁם מִתְבָּאֵר בְּמַאי פְלִיגִי. And this prohibition is practiced in every place and at all times. And [in a case of a man] who transgresses it and laid with a woman and with her daughter, both of them are burnt — he and the one he laid with last. As the first one has no sin, since [it was] permitted [for] him [to] marry her. And if he had intercourse with the second after the death of his first wife, behold they are [punished] with excision and they do not [receive] a death penalty of the court. As it is stated in another place in the Order of Kedoshim Tehiyu (Leviticus 20:14), “they shall be burned with fire, he and them (et’hen).” And Rabbi Eliezer explained in Sanhedrin 66b, “‘They shall be burned with fire, he and’ one of them (echat mehen)’” — which is the later one, as we said. But that is only when both of them are alive — as so came the explanation. But when both of them are not alive, there is no burning there. Rather, they are [punished] with a liability for excision when volitional; and he brings a fixed sin-offering when inadvertent. However Rabbi Akiva explains there, “He and both of them” — for example that he [was] forbidden to marry both of them, and this is found when he married a daughter, her mother and the mother of her mother. And what they disagree about is explained there.