Mishnah Niddah
1א׳
1 א

שַׁמַּאי אוֹמֵר, כָּל הַנָּשִׁים דַּיָּן שְׁעָתָן. הִלֵּל אוֹמֵר, מִפְּקִידָה לִפְקִידָה, וַאֲפִלּוּ לְיָמִים הַרְבֵּה. וַחֲכָמִים אוֹמְרִים, לֹא כְדִבְרֵי זֶה וְלֹא כְדִבְרֵי זֶה, אֶלָּא מֵעֵת לְעֵת מְמַעֵט עַל יַד מִפְּקִידָה לִפְקִידָה, וּמִפְּקִידָה לִפְקִידָה מְמַעֶטֶת עַל יַד מֵעֵת לְעֵת. כָּל אִשָּׁה שֶׁיֶּשׁ לָהּ וֶסֶת, דַּיָּהּ שְׁעָתָהּ. וְהַמְשַׁמֶּשֶׁת בְּעִדִּים, הֲרֵי זוֹ כִפְקִידָה, וּמְמַעֶטֶת עַל יַד מֵעֵת לְעֵת וְעַל יַד מִפְּקִידָה לִפְקִידָה:

Shammai says: for all women it suffices [to reckon] their [period of uncleanness from their time [of discovering the flow]. Hillel ruled: [their period of uncleanness is to be reckoned retroactively] from the [previous] examination to the [last] examination, even if this was many days. The sages say: [the law is] not like the words of these or the words of those, but [the women are deemed to have been unclean] during [the preceding] twenty-four hours when this lessens the period from the [previous] examination to the [last] examination, and during the period from the [previous] examination to the [last] examination when this lessens the period of twenty-four hours. For any woman who has a regular period it suffices [to reckon her period of uncleanness from] the time she discovers the flow. And if a woman uses rags when she has marital intercourse, this is like an examination which lessens either the period of the [past] twenty-four hours or the period from the [previous] examination to the [last] examination.

2 ב

כֵּיצַד דַּיָּהּ שְׁעָתָהּ. הָיְתָה יוֹשֶׁבֶת בַּמִּטָּה וַעֲסוּקָה בְטָהֳרוֹת, וּפֵרְשָׁה וְרָאֲתָה, הִיא טְמֵאָה וְכֻלָּן טְהוֹרוֹת. אַף עַל פִּי שֶׁאָמְרוּ, מְטַמְּאָה מֵעֵת לְעֵת, אֵינָהּ מוֹנָה אֶלָּא מִשָּׁעָה שֶׁרָאָתָה:

How [does the rule that] it suffices [to reckon her period of uncleanness from] the time she discovers the flow work? If she was sitting on a bed and was occupied with ritually clean objects and then she leaves [the bed] and then sees [blood flow] she is unclean but the objects are clean. Even though they have said that she conveys uncleanness for a period of twenty-four hours [retroactively] she counts [the seven days of her menstruation] only from the time she observed the flow.

3 ג

רַבִּי אֱלִיעֶזֶר אוֹמֵר, אַרְבַּע נָשִׁים דַּיָּן שְׁעָתָן, בְּתוּלָה, מְעֻבֶּרֶת, מֵנִיקָה וּזְקֵנָה. אָמַר רַבִּי יְהוֹשֻׁעַ, אֲנִי לֹא שָׁמַעְתִּי אֶלָּא בְתוּלָה, אֲבָל הֲלָכָה כְּרַבִּי אֱלִיעֶזֶר:

Rabbi Eliezer says: there are four types of women for whom it suffices [to reckon] their [period of uncleanness from] the time [of their discovering the flow]. A virgin, A pregnant woman, A nursing woman; And an old woman. Rabbi Joshua says: I have only heard [the ruling applied to] a virgin, but the halakhah is in agreement with Rabbi Eliezer.

4 ד

אֵיזוֹ הִיא בְתוּלָה, כֹּל שֶׁלֹּא רָאֲתָה דָם מִיָּמֶיהָ, אַף עַל פִּי שֶׁנְּשׂוּאָה. מְעֻבֶּרֶת, מִשֶּׁיִּוָּדַע עֻבָּרָהּ. מֵנִיקָה, עַד שֶׁתִּגְמֹל אֶת בְּנָהּ. נָתְנָה בְנָהּ לְמֵנִיקָה, גְּמָלַתּוּ אוֹ מֵת, רַבִּי מֵאִיר אוֹמֵר, מְטַמְּאָה מֵעֵת לְעֵת. וַחֲכָמִים אוֹמְרִים, דַּיָּהּ שְׁעָתָהּ:

Who is regarded as "virgin"? Any woman who has never yet observed a blood flow, even if she is married. "A woman in pregnancy"? One whose fetus is notice. "A nursing woman"? Until she has weaned her child. If she gave her child to a nursing woman, if she weaned him, or if he died: Rabbi Meir says: she conveys uncleanness retroactively for twenty-four hours; But the sages say: it suffices for her [to reckon her period of uncleanness from] the time of her [observation of the flow].

5 ה

אֵיזוֹהִי זְקֵנָה. כֹּל שֶׁעָבְרוּ עָלֶיהָ שָׁלשׁ עוֹנוֹת סָמוּךְ לְזִקְנָתָהּ. רַבִּי אֱלִיעֶזֶר אוֹמֵר, כָּל אִשָּׁה שֶׁעָבְרוּ עָלֶיהָ שָׁלשׁ עוֹנוֹת, דַּיָּהּ שְׁעָתָהּ. רַבִּי יוֹסֵי אוֹמֵר, מְעֻבֶּרֶת וּמֵנִיקָה שֶׁעָבְרוּ עֲלֵיהֶן שָׁלשׁ עוֹנוֹת, דַּיָּן שְׁעָתָן:

Who is regarded as "an old woman"? Any woman over whom three "onot" have passed near the time of her old age. Rabbi Eliezer says: for any woman over whom have passed three onot it suffices [to reckon her period of uncleanness from] the time of her [observing a flow]. Rabbi Yose says: for a woman in pregnancy and a nursing woman over whom three onot have passed it suffices [to reckon their period of uncleanness from] the time of their [observation of the flow].

6 ו

וּבַמֶּה אָמְרוּ דַּיָּהּ שְׁעָתָהּ. בִּרְאִיָּה רִאשׁוֹנָה. אֲבָל בַּשְּׁנִיָּה, מְטַמְּאָה מֵעֵת לְעֵת. וְאִם רָאֲתָה הָרִאשׁוֹנָה מֵאֹנֶס, אַף הַשְּׁנִיָּה דַּיָּהּ שְׁעָתָהּ:

And of what did they speak when they said that "it suffices [for them to reckon] their period of uncleanness from the time [of their discovering of the flow]"? [This refers to] the first observation, but after a second observation she defiles retroactively for a period of twenty-four hours. If she saw the first flow on account of an accident even it suffices for her even a subsequent observation [to reckon her uncleanness from] the time of her [observing of the flow].

7 ז

אַף עַל פִּי שֶׁאָמְרוּ דַּיָּהּ שְׁעָתָהּ, צְרִיכָה לִהְיוֹת בּוֹדֶקֶת, חוּץ מִן הַנִּדָּה וְהַיּוֹשֶׁבֶת עַל דַּם טֹהַר. וּמְשַׁמֶּשֶׁת בְּעִדִּים, חוּץ מִיּוֹשֶׁבֶת עַל דַּם טֹהַר, וּבְתוּלָה שֶׁדָּמֶיהָ טְהוֹרִים. וּפַעֲמַיִם צְרִיכָה לִהְיוֹת בּוֹדֶקֶת, בְּשַׁחֲרִית וּבֵין הַשְּׁמָשׁוֹת, וּבְשָׁעָה שֶׁהִיא עוֹבֶרֶת לְשַׁמֵּשׁ אֶת בֵּיתָהּ. יְתֵרָה עֲלֵיהֶן כֹּהֲנוֹת, בְּשָׁעָה שֶׁהֵן אוֹכְלוֹת בַּתְּרוּמָה. רַבִּי יְהוּדָה אוֹמֵר, אַף בִּשְׁעַת עֲבָרָתָן מִלֶּאֱכֹל בַּתְּרוּמָה:

Although though they said [that for a woman who has a regular period] it suffices to reckon her period of uncleanness from the time she observes a flow, she should nevertheless examine herself [regularly], except for a menstruant or one who is sitting over pure blood. She should also use testing-rags when she has marital intercourse except when she is sitting over pure blood or when she is a virgin whose blood is clean. And twice [daily] she should examine herself: in the morning and at the [evening] twilight, and also when she is about to have sexual relations. Priestly women are subject to an additional restriction [for they should examine themselves] when they are going to eat terumah. Rabbi Judah said: [these must examine themselves] also after they have concluded eating terumah.