Mishnayos Niddah Perek 10 Mishnah 8

There is a dispute with regard to a woman who sees blood on the eleventh day, which is the final day of the period fit for the flow of a zava. It is permitted for her to engage in intercourse with her husband after observing one clean day corresponding to the one day that she saw blood, but in this case, she failed to observe one clean day. Rather, she immersed in a ritual bath that evening, the eve of the twelfth day, and then engaged in intercourse with her husband. Beit Shammai say: Since she did not observe that corresponding clean day, she retains the status of a zava. Therefore both she, the zava, and her husband, who engaged in intercourse with a zava, transmit impurity to items designated for lying or sitting, to the extent that these transmit impurity to food and drink that came in contact with them, and in her case, to people as well. And each of them is liable to bring a sin offering for participating in intercourse involving a zava. And Beit Hillel say: Although they transmit impurity to items designated for lying or sitting, they are exempt from bringing the sin offering. Since the twelfth day is unfit for the flow of a zava, and even if she were to experience bleeding on the eleventh, twelfth, and thirteenth days she would not become a greater zava, one who experiences bleeding on the eleventh does not need to observe a corresponding clean day. If the woman immersed on the day following the eleventh day and she engaged in intercourse with the man of her house, i.e., her husband, on that twelfth day and then saw blood, Beit Shammai say: They transmit impurity to items designated for lying or sitting by rabbinic law, as the Sages issued a decree of impurity in the case when the second day is the twelfth day, due to a case when the second day is within the eleven days fit for the flow of a zava. And they are exempt from bringing the sin offering, as she observed part of the twelfth day, and the bleeding she experienced after engaging in intercourse, which occurred during her period of menstruation, is not fit to be appended to the discharge of the zava on the eleventh day. And Beit Hillel say: That husband is a glutton, as he could not wait for the conclusion of the twelfth day before engaging in intercourse. Nevertheless, the Sages did not issue a decree of impurity. And Beit Hillel concede to Beit Shammai in a case where the woman sees blood in the midst of the eleven-day period, and she immersed in the evening and engaged in intercourse with her husband without observing a corresponding clean day, that they transmit impurity to items designated for lying or sitting. And each of them is liable to bring a sin offering for participating in intercourse involving a zava. If she saw blood in the midst of the eleven days and observed part of a corresponding clean day and immersed on the day following the day that she saw blood and engaged in intercourse with her husband, that is wayward conduct, as the possibility exists that she will experience bleeding after intercourse that will be appended to the bleeding of the previous day, rendering her a zava and disqualifying the immersion. And the status of ritually impure items with which they came into contact and the status of their intercourse is contingent upon whether she experiences bleeding on the day of her immersion, in which case the ritually pure items become impure and they are liable to bring a sin offering, or whether she does not experience bleeding that day, in which case the ritually pure items remain pure and the woman and man are exempt from bringing a sin offering.

הָרוֹאָה יוֹם אַחַד עָשָׂר וְטָבְלָה לָעֶרֶב וְשִׁמְּשָׁה, בֵּית שַׁמַּאי אוֹמְרִים, מְטַמְּאִין מִשְׁכָּב וּמוֹשָׁב, וְחַיָּבִין בַּקָּרְבָּן. וּבֵית הִלֵּל אוֹמְרִים, פְּטוּרִין מִן הַקָּרְבָּן. טָבְלָה בַיוֹם שֶׁלְּאַחֲרָיו וְשִׁמְּשָׁה אֶת בֵּיתָהּ וְאַחַר כָּךְ רָאֲתָה, בֵּית שַׁמַּאי אוֹמְרִים, מְטַמְּאִין מִשְׁכָּב וּמוֹשָׁב וּפְטוּרִים מִן הַקָּרְבָּן. וּבֵית הִלֵּל אוֹמְרִים, הֲרֵי זֶה גַרְגְּרָן. וּמוֹדִים בְּרוֹאָה בְתוֹךְ אַחַד עָשָׂר יוֹם וְטָבְלָה לָעֶרֶב וְשִׁמְּשָׁה, שֶׁמְּטַמְּאִין מִשְׁכָּב וּמוֹשָׁב וְחַיָּבִין בַּקָּרְבָּן. טָבְלָה בַיּוֹם שֶׁלְּאַחֲרָיו וְשִׁמְּשָׁה, הֲרֵי זוֹ תַרְבּוּת רָעָה, וּמַגָּעָן וּבְעִילָתָן תְּלוּיִים: