ב הַמְקַדֵּשׁ שְׁתֵּי נָשִׁים כְּאַחַת, שֶׁאָסוּר לִשָּׂא שְׁתֵּיהֶן מִשּׁוּם עֶרְוָה, אֵינָן מְקֻדָּשׁוֹת. כֵּיצַד, כְּגוֹן שֶׁקִּדֵּשׁ אִשָּׁה וּבִתָּהּ, אוֹ שְׁתֵּי אֲחָיוֹת כְּאַחַת, שֶׁאָמַר: הֲרֵי שְׁתֵּיכֶן מְקֻדָּשׁוֹת לִי, אֵינָן מְקֻדָּשׁוֹת וְאֵין שׁוּם אַחַת מֵהֶן צְרִיכָה גֵּט. וְאִם לֹא קִדֵּשׁ אֶלָּא אַחַת, וְלֹא פֵּרַשׁ אֵיזוֹ, כְּגוֹן שֶׁאָמַר לְאָב: אַחַת מִבְּנוֹתֶיךָ מְקֻדֶּשֶׁת לִי, וְקִבֵּל הָאָב הַקִּדּוּשִׁין, אוֹ אִם שְׁתַּיִם אוֹ שָׁלשׁ אֲחָיוֹת עָשְׂתָה אַחַת מֵהֶן שָׁלִיחַ לַחֲבֶרְתָּהּ לְקַבֵּל קִדּוּשֶׁיהָ, וְנָתַן בְּיָדָהּ, וְאָמַר לָהּ: אַחַת מִכֵּן מְקֻדֶּשֶׁת לִי, כֻּלָּן צְרִיכוֹת גֵּט מִמֶּנּוּ, וְאָסוּר לָבוֹא עַל שׁוּם אַחַת מֵהֶן, שֶׁמָּא הִיא אֲחוֹת אִשְׁתּוֹ:
2 One who betroths two women at once, both of whom he is forbidden to betroth because of ervah (forbidden relationships), they are not betrothed. How so? As in the case of one who betrothed a woman and her daughter, or two sisters at once, who said: Behold you are both betrothed to me, they are not betrothed and neither one of them needs a get. But if he only betrothed one, and did not specify which, as [is the case if] he said to the father: One of your daughters is betrothed to me, and the father accepted the betrothal, or if two or three sisters made one of themselves an emissary for her counterpart to accept her betrothal, and he gave it into her hand and said to her: One of you is betrothed to me, they all require a get from him, and it is forbidden for him to have relations with any of them, lest she is the sister of his wife.