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Zev Farber





The Purification of a Niddah: The Torah Requirement





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Zev Farber





The Purification of a Niddah: The Torah Requirement








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The Purification of a Niddah: The Torah Requirement


The Purification of a Niddah: The Torah Requirement


According to halacha, a married woman must immerse herself in a mikvah (ritual bath) after her period.[1] Halakhic literature characterizes this practice as de-oraitta, a commandment with a basis in the Torah. In his Shulchan Aruch, Laws of Niddah (Yoreh Deah 197:1), Rabbi Joseph Karo writes:

אין הנדה והזבה והיולדת עולות מטומאתן בלא טבילה, שאפילו אחר כמה שנים חייב כרת הבא על אחת מהן אלא אם כן טבלו כראוי במקוה הראוי.
A niddah (menstruant), a zavah (woman with an unusual flux), or a yoledet (woman who just gave birth) cannot leave her state of impurity without immersion (in the waters of a mikvah). Even years later, any man who has relations with such a woman will receive the punishment of excision unless she has gone to the mikvah properly.

The strident position of Jewish law on this issue masks a surprising fact: The Torah makes no mention whatsoever of a niddah being required to immerse in water.[2] To appreciate the magnitude of the Torah’s silence on this, let us compare the purification of a niddah according to the biblical text with the purification process of people experiencing other types of genital flow–based impurity.

Part 1

Flow Impurities and Their Purification Rituals in Leviticus

Leviticus 15 lists a number of genital flow–based impurities, for men and women, along with a description of how each person should go about purifying him- or herself.

Zav (vv. 1-15)

Zav refers to male non-seminal discharge (presumably gonorrhea or some other sexually transmitted disease). To purify himself, the man must wait seven days after the discharge has ceased, wash his clothes, bathe his body in fresh (i.e., running) water, and bring two turtledoves or pigeons as an expiation offering. Furthermore, the zav renders things that he touches or sits upon impure, and any person who comes in contact with a zav or with one of these objects becomes impure and must wash his or her clothes and his or her body in water, becoming pure again in the evening.

Seminal emissions (vv. 16-18)

A man who has a seminal emission apart from sex must wash himself and is pure that evening. Any clothing upon which the semen falls must be washed as well. If a man and woman have sexual relations (v. 18), both must wash themselves and are then pure in the evening.

Niddah (vv. 19-24)

When a woman has her period, she is impure for seven days. The Torah does not prescribe any purification process here. If a man lies with a menstruating woman, he receives the same impurity and is impure for seven days. If a person touches her, that person is rendered impure until evening. No purification process is prescribed for either of these cases. Any object with which the woman comes in contact becomes unclean, and any person who comes in contact with an object she has rendered impure becomes impure himself or herself. In this last case, the person must wash himself or herself and his or her clothing and then will be pure in the evening.

Zavah (vv. 25-30)

Zavah refers to a woman who has an abnormal bloody flow. To purify herself she must wait seven days after the flow has ceased and then bring two turtledoves or pigeons as an expiation offering. There is no mention of washing in water. Anything she touches becomes impure, and whoever touches those objects becomes impure. He or she must wash his or her clothing and body in water and then will become pure again in the evening.

Looking at the above text schematically, some basic principles stand out. First, for both men and women there are two kinds of genital impurity, regular (ejaculation and menstruation) and irregular (zav and zavah). This is underlined by the chiastic structure (ABBA) of the pericope, with the discussion of the two irregular emissions flanking the discussion of the two regular emissions. Purification from the irregular emission requires an expiation offering. Presumably, this is because the Torah sees a possible connection between illness and sin (in the case of sexually transmitted diseases, such a connection may be likely). Additionally, the abnormal flows require a waiting period of a week in order to ensure that the illness is really gone.

Another principle is that male genital impurities require washing as part of the purification process. For an abnormal flow, fresh or running water is required; for a seminal emission, any water is acceptable. For a woman to purify herself from her emissions, on the other hand, no washing is needed. A niddah is automatically pure after seven days from the start of her flow, and a zavah is automatically pure after seven days from the end of her flow.

The third principle is that impurity from coming in contact with one of these people is gender neutral. A man who is intimate with a niddah contracts “niddah” in a manner of speaking and needs to wait seven days to become (automatically) purified. Conversely, a woman who is intimate with a man receives the same impurity as he does from the seminal emission. Finally, anyone, man or woman, who comes in contact with something that became impure from one of these people becomes impure for the remainder of the day and must wash his or her body and clothes.

Turning the focus back to niddah and zavah, it seems clear from the biblical text that there is no need for women impure from flow to immerse in water of any kind. I speculate that this could be due to a social reality where men visit the Temple/altar more frequently than women do and thus have more rigorous standards of purity. Nevertheless, since the Priestly laws has both men and women bringing sacrifices and Priests and Levites doing all the sacrifices, this speculation may be erroneous. The bottom line is that the Torah describes the purification requirements for every case of genital flow in this chapter and mentions washing numerous times. If the niddah or zavah required washing, the Torah would have said so explicitly.

Part 2

Creating the Immersion Requirement for Women in Rabbinic Judaism

In rabbinic Judaism, it is a given that women immerse themselves after their periods. Where this idea originated is unclear. It may be that this practice existed in biblical times and represents an alternative to the practice reflected in the Priestly text of Leviticus. For example, in the famous story of David and Bathsheba (2 Sam. 11:2-4), David sees Bathseba רוחצת "washing with water" as she sanctified herself from her impurity.”[3] Presumably, the story is telling the reader that she was washing herself as part of a purification ritual to remove the impurity of niddah.

Alternatively, this may be a natural expansion of the male purification ritual to include women. In the Second Temple period, water was more readily available and bathing was popular. Considering the underlying physical reality that washing is a way of producing actual physical cleanliness and that women after their periods would most probably want to get clean—especially before the invention of feminine products—there is good reason to assume that women who had access to baths would use them after their periods. (This could be true of First Temple period women with access to water as well, which would explain the Bathsheba story.) Combined with the strong focus on purity in the late Second Temple period, this provides ample reason to extend the washing ritual to women.[4]

For the Rabbis there would have been an even stronger impetus. Since the laws of purity and impurity became largely theoretical in rabbinic Judaism after the destruction of the Temple, niddah took on extra importance. Since according to Lev. 18:19 and 20:18 it is forbidden for a man to have relations with a niddah, this particular purity law outlived the others. A ritual separating the state of niddah from the state of purity may have become more significant, since this would be the only purification ritual remaining as lived experience.

Whether or not the above speculations have any merit, the fact remains that the Rabbis believed that women required immersion to become pure. The problem was that the Torah says no such thing. How did the Rabbis defend their practice? They did so through midrash.

Part 3

Midrashic Proofs That a Niddah or Zavah Must Wash to Become Pure

Suggestion 1 – Rabbi Akiva

The earliest midrash defending the immersion of a niddah as a requirement comes from a baraita in the Babylonian Talmud (Shabbat 64b) and the Sifra (Zavim 5:12). The midrash is glossing a phrase in the concluding verses of Lev. 15:

לב זֹאת תּוֹרַת הַזָּב וַאֲשֶׁר תֵּצֵא מִמֶּנּוּ שִׁכְבַת זֶרַע לְטָמְאָה בָהּ. לג וְהַדָּוָה בְּנִדָּתָהּ וְהַזָּב אֶת זוֹבוֹ לַזָּכָר וְלַנְּקֵבָה וּלְאִישׁ אֲשֶׁר יִשְׁכַּב עִם טְמֵאָה.
32 Such is the ritual concerning him who has a discharge: concerning him who has an emission of semen and becomes unclean thereby, 33 and concerning her who is in menstrual infirmity, and concerning anyone, male or female, who has a discharge, and concerning a man who lies with an unclean woman.

Picking up on the term “menstrual infirmity,” the baraita states:

והדוה בנדתה – חסידים הראשונים אמרו שלא תכחול ושלא תתפרכס ושלא תקשט בבגדי צבעונין, עד שבא ר’ עקיבא ולימד: “אם כן נמצאת [אתה] מגנה על בעלה ונמצא בעלה מגרשה אלא מה ת”ל והדוה בנדתה בנדתה תהא עד שתבא במים” (כתב יד מינכן 95).
“She who is in menstrual infirmity”—the ancient elders used to say that [this phrase teaches] that a woman may not put on eyeliner, makeup, or colored clothing [while she is in her impurity], until Rabbi Akiva came and taught thus: “You will end up making her repulsive to her husband and her husband may divorce her. Rather, what does ‘she who is in her menstrual infirmity’ come to teach? She shall remain in her menstrual state until she immerses in water.”

In this source, Rabbi Akiva reads the verse about “menstrual infirmity” as an oblique reference to the requirement for a woman to immerse in water in order to remove that status.[5] For Rabbi Akiva, the usefulness of this reading is in its canceling the alternative reading of the elders that a menstruating woman should be forbidden to wear makeup or dress nicely.

How are we to understand Rabbi Akiva’s midrash? A radical interpretation would be that Rabbi Akiva invented the requirement for women to immerse in water after niddah as a way of counteracting a practice he considered abhorrent (forcing women to remain unadorned, even at the risk of upsetting their husbands.)[6] A more moderate suggestion would be that there was already a practice of women immersing in water after niddah/zavah, and that Rabbi Akiva was simply finding some sort of biblical basis for this practice.[7]

Either way, Rabbi Akiva’s midrash highlights the obvious problem: there is no biblical basis for this practice without a hermeneutical deduction of sorts.[8] The midrashic nature of Rabbi Akiva’s deduction demonstrates that the Talmud is well aware that there is no “smoking gun” verse proving a requirement for niddot/zavot to immerse in water.

Suggestion 2 – Rav Yehudai Gaon

The suggestion with the most “common sense” backing comes from R. Yehudai Gaon (8th century). Section 45 of the collection of Geonic responsa edited by Jacob Musafia (Lyck) lists a host of questions answered by R. Yehudai Gaon. One of them is about immersion for a niddah:

תוב שמ”ק טבילה לנדה מן התורה מנין. ואמר קל וחומר ממגעה.
They asked him another matter: “Where does the immersion of a niddah appear in the Torah?” He answered: “It is an a fortiori argument from contact with her (which requires washing).”

Aware that the Torah nowhere actually says that a niddah should immerse in water, R. Yehudai constructs a logical argument. Since according to Lev. 15, if someone touches something that a niddah touched, he or she must wash him- or herself to become pure, then certainly the niddah herself would need to do so.[9]

Excursus: A Critique of Milgrom’s Position

One fascinating fact about this argument is that it finds support from one of the greatest academic scholars of Leviticus, Jacob Milgrom. In his monumental Anchor Bible commentary on Leviticus (vol. 1, p. 935), Milgrom makes the same argument as Rav Yehudai, stating that the text simply assumes that the woman must immerse herself in water.[10]This is, to me, a fascinating convergence between medieval midrash and modern scholarship.

Nevertheless, when one considers this argument in the context of the other impurity laws mentioned in the very same chapter, I believe the explanation does not hold up. In the laws of the man who is a zav or has a seminal emission, the requirement for someone who comes in contact with him or something he touches to wash is mentioned no less than eight times—and still the Torah takes the time to state that the man himself must wash. It is hard to believe that the Torah suddenly became parsimonious with words when it came to legislation for the woman.

The way I understand this is that the woman does not need to wash since her impurity goes away automatically when her period ends, or seven days after a non-menstrual flow ends. When it comes to things that she touched, however, the usual impurity rules apply. Perhaps this is because when the object becomes impure it loses the special status of niddah or zavahimpurity and becomes just an impure object, calling for the usual rules. In support of this interpretation, it is notable that the text says nothing about a person who touches a niddah or zavah or a man who is intimate with her having to wash. The former is impure for the rest of the day, the latter for seven days. I assume this has to do with mirroring the woman’s impurity: since she does not have to wash, he does not have to, either.

Suggestion 3 – Rabbeinu Tam

Another possible biblical source for the requirement of a niddah to immerse in water was put forward by R. Jacob ben Meir of Ramerupt, better known as Rabbeinu Tam (1100-1171). Rabbeinu Tam points to a passage in the Babylonian Talmud (Avodah Zarah 75b) which glosses the phrase “waters of niddah.” The verse being glossed is Numbers 31:23, which discusses what must be done with the cooking vessels taken from the slaughtered Midianites:

כָּל־דָּבָ֞ר אֲשֶׁר־יָבֹ֣א בָאֵ֗שׁ תַּעֲבִ֤ירוּ בָאֵשׁ֙ וְטָהֵ֔ר אַ֕ךְ בְּמֵ֥י נִדָּ֖ה יִתְחַטָּ֑א וְכֹ֨ל אֲשֶׁ֧ר לֹֽא־יָבֹ֛א בָּאֵ֖שׁ תַּעֲבִ֥ירוּ בַמָּֽיִם:
Any article that can withstand fire—these you shall pass through fire and they shall be clean, except that they must be cleansed with waters of niddah; and anything that cannot withstand fire you must pass through water.

The Talmud interprets the phrase “waters of niddah” as “waters in which a niddah immerses,” i.e., a volume of forty seah. Picking up on this, R. Tam suggests that this may be the source for the Torah law requiring a niddah to immerse herself in water in order to be purified.

As a midrash, this explanation works well. Nevertheless, from a peshat perspective this is almost certainly not what the verse means. The “waters of niddah” are referenced in one other place, the ritual for purifying individuals who have come in contact with a corpse, which involves sprinkling water mixed with the ashes of a red heifer (Num. 19:9). After explaining how to make the concoction, the Torah states:

וְאָסַ֣ף׀ אִ֣ישׁ טָה֗וֹר אֵ֚ת אֵ֣פֶר הַפָּרָ֔ה וְהִנִּ֛יחַ מִח֥וּץ לַֽמַּחֲנֶ֖ה בְּמָק֣וֹם טָה֑וֹר וְ֠הָיְתָה לַעֲדַ֨ת בְּנֵֽי־ יִשְׂרָאֵ֧ל לְמִשְׁמֶ֛רֶת לְמֵ֥י נִדָּ֖ה חַטָּ֥את הִֽוא:
A man who is clean shall gather up the ashes of the cow and deposit them outside the camp in a clean place, to be kept for water of niddah for the Israelite community. It is for cleansing.

In other words, the phrase “waters of a niddah” is the technical term for the red heifer concoction. As pointed out by Rashi, Rashbam, and R. Abraham ibn Ezra, the simple meaning of the text is that the vessels of the Midianites need to be purified from corpse contamination, ostensibly because there was just a battle in the area and their previous owners have just been slaughtered. Thus, the Talmud’s reading is midrashic and does not reflect the peshat of the text.

Suggestion 4 – Rambam

In his Mishneh Torah (Kodshim, “Issurei Biah” 4:3), Rambam, following the Geonim,[11] offers yet another midrashic origin for this rule. Rambam turns to Lev. 15:18, which refers to purification after coitus:

וְאִשָּׁ֕ה אֲשֶׁ֨ר יִשְׁכַּ֥ב אִ֛ישׁ אֹתָ֖הּ שִׁכְבַת־זָ֑רַע וְרָחֲצ֣וּ בַמַּ֔יִם וְטָמְא֖וּ עַד־הָעָֽרֶב:
And if a man has carnal relations with a woman, they shall wash in water and remain unclean until evening.

Referring to the requirement for niddot, zavot, and yoladot to immerse in water as part of their purification, Rambam explains that this rule comes from a midrash on this verse.

ורחצו במים זה בנין אב לכל טמא שהוא בטומאתו עד שיטבול.
“And they shall wash in water”—this is a paradigmatic verse (binyan av) for any person who is impure, that he (or she) remain impure until he (or she) immerses (in a mikvah).

This reading works as midrashic support for the practice of a niddah washing, but it is not plausible as a peshat explanation of the verse. The simple meaning of the verse has to do specifically with seminal emissions.

Earlier in Lev. 15, there is a discussion of seminal emissions outside the context of sex, presumably nocturnal emissions. The Torah then turns to the more standard case of sex to say that this still makes the man impure but affects the woman as well. There is little reason to assume that this verse was meant to apply to the niddah and zavah, when these cases will be given a relatively full treatment in the same chapter. It is worth reiterating that the need to wash is mentioned at least ten times in this chapter. Thus it is difficult to claim, as a matter of peshat, that Leviticus only wishes to mention washing once and then works with the assumption that the reader will fill in the gaps for the rest of the cases in the chapter.


The above varying, late midrashic efforts to anchor immersion for a niddah and zavah in the Torah highlight the opposite, that this practice has no explicit basis in the Torah. Nevertheless, Judaism views the practice of immersion after menstruation as de-oraitta.

Perhaps, as evidenced by the Bathsheba story, at least washing oneself was a common practice among certain Israelites/Jews going back into the First Temple period. When this practice became universal is unknown, but certainly the Rabbis take it for granted, as do the Karaites and the Samaritans.

Once the practice of washing developed into the ritual of mikvah, it is hardly surprising that there would be a strong religious urge to place a niddah’s washing under this rubric, as a ritual of purification. Only at this point, I believe, once the practice became sufficiently widespread, did the Rabbis begin to feel the need to fit it in with the biblical verses, thereby creating the midrashic underpinnings for the ancient practice of washing or immersion after niddah.

For Jews today—and for the last 2000 years—mikvah is a practice predominantly associated with women.[12] It is virtually synonymous with “the end of the niddah state” for women. Although the origins of this practice are obscure, washing or immersion in water has changed from a mostly male ritual focusing on purity and the Temple into a mostly female ritual focusing on sexual availability and marriage.

The Purification of a Niddah

Next: “The Legal Responsibility of the Reader” by Dr. Yitzhaq Feder


April 3, 2014


Last Updated

December 29, 2021


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Dr. Rabbi Zev Farber is the Senior Editor of TheTorah.com, and a Research Fellow at the Shalom Hartman Institute's Kogod Center. He holds a Ph.D. from Emory University in Jewish Religious Cultures and Hebrew Bible, an M.A. from Hebrew University in Jewish History (biblical period), as well as ordination (yoreh yoreh) and advanced ordination (yadin yadin) from Yeshivat Chovevei Torah (YCT) Rabbinical School. He is the author of Images of Joshua in the Bible and their Reception (De Gruyter 2016) and editor (with Jacob L. Wright) of Archaeology and History of Eighth Century Judah (SBL 2018).