Niddah נדה

Nidda is the only tractate in Seder Teharot, the Order of Ritual Purity, for which there is a tractate of Gemara, in addition to its mishnayot, both in the Babylonian Talmud and a slim volume in the Jerusalem Talmud. The rest of the many and large tractates in this order have no Gemara written on them at all. The reason for this is that when the Temple was destroyed, the halakhot of ritual purity discussed in Seder Teharot became largely inapplicable. As the connection to the Temple and its concepts became increasingly distant, the necessity of studying Teharot correspondingly diminished. An exception to this trend is the study of the tractates in Seder Kodashim, which discusses the Temple and its offerings; the study of Kodashim can be understood as an expression of the eternal hope in the rebuilding of the Temple and of the redemption. The study of Teharot, which deals with the halakhot of ritual purity that are merely affiliated with the Temple, does not represent the same hope and indefatigable yearning.

The exception within Seder Teharot is tractate Nidda, as the status of a menstruating woman includes two aspects: One is that such a woman assumes ritual impurity status and transmits impurity. Her touch disqualifies consecrated items and renders ritually pure items impure. This aspect is similar to the other halakhot of impurity discussed throughout Seder Teharot. The second aspect is the status of a menstruating woman as one with whom intercourse is strictly forbidden, to the point that a man and woman who transgress this prohibition are liable to receive the grave punishment of karet. Although the first aspect of ritual impurity is just as impractical as the rest of Teharot, this second aspect of forbidden intercourse remains as applicable as ever. It is therefore necessary to delve into these halakhot and clarify them in every respect, in order to establish the halakha in practice.

This tractate deals not only with the halakhot of a menstruating woman, but also with a series of other related halakhot that have some connection to a menstruating woman. Many of these topics have no other corpus where they are elucidated in full. The halakhot concerning a menstruating woman are derived, in the main, from the verse: “And if a woman has an issue, and her issue in her flesh is blood, she shall be in her menstruation seven days, and whoever touches her shall be impure until the evening.” (Leviticus 15:19). The subject closest to the case of a menstruating woman is a zava (see Leviticus 15:25-30). The discharge of ziva that applies to women has no medical similarity to that of a male zav. Whereas the ziva of a man is a specific, known condition with its own specifications, the ziva found in women is defined as the discharge of uterine blood not at the time of her menstruation. The status of a zava is generally even more stringent than that of a menstruating woman, as a greater zava requires a longer period of time to attain a status of purity: Seven days during which absolutely no blood is found. In addition, she must bring offerings upon the completion of her purification period.

A different type of ritual impurity is caused by the flow of blood of a woman after childbirth. The Torah states (see Leviticus 12:1-8) that there is a specific period of time after childbirth when any blood that the mother discharges has the same status as menstrual blood. Following that period of impurity there is a period of blood of purity, during which any blood that she emits does not transmit impurity. Different periods of impurity and purity are prescribed in accordance with the sex of the baby. A woman after childbirth is also required by Torah law to bring offerings after that period of purity, and only after their sacrifice is she permitted to partake of consecrated food and enter the Temple.

In addition to these categories of blood that transmit impurity by Torah law, there are other types of blood that exit via the vagina that do not transmit impurity by Torah law. They are blood from a torn hymen and blood from a wound along the vaginal canal. These types of blood are free of impurity, but one is not always able to distinguish between different types of blood to determine if blood that is found in that area is impure, pure, or a mixture of the two.

The Torah teaches what kinds of blood transmit impurity and which halakhot govern each particular type of blood. The discharges of these various types of blood are tangible, physical occurrences, and the ability to clarify and investigate physical phenomena is accessible to the experts of each generation.

Nevertheless, due to the grave nature of these prohibitions, the transgression of which can entail the punishment of karet, the Sages throughout the generations have cautioned and safeguarded not only against clear prohibitions, but also against any cases of uncertainty. One result of such concerns is that even the examinations recommended by the Talmud were not always relied upon in practice if they led to lenient rulings. Some of these examinations entail fine distinctions between shades of blood, and at times even differences in form or smell, and these distinctions cannot easily be expressed in words. Therefore, there is always a concern that our expertise in these areas might be lacking, and the tendency is to err on the side of caution when rendering practical rulings.

Tractate Nidda also analyzes the length of a woman's menstrual cycle. There are seven days of ritual impurity status caused by any discharge of menstrual blood, whether it flows throughout the seven days or only on some of them. This is followed by a period of purity that spans eleven days in between each period of menstruation. During that time, blood that a woman emits is not considered menstrual blood. If she does experience bleeding, it is defined as ziva blood, to which a different set of halakhot apply. Although there may be differences in practice, this cycle of seven days followed by eleven days is a set system with regard to the various halakhot of a menstruating woman and a zava that is accepted as a halakha transmitted to Moses from Sinai.

These fixed halakhic definitions and established principles often become confusing when applied to real-life scenarios. Menstrual cycles are complex and irregular. This is true not only of women in general, but even with regard to each woman's individual cycle. Whereas some woman have fixed, immutable menstrual cycles, both with regard to the dates on which menstruation occurs and its duration, others have more sporadic, variable cycles that are unpredictable both with regard to duration as well as the dates on which menstruation occurs or does not occur. Time is of utmost importance in this regard, as it is imperative to know in advance exactly when a woman may assume ritual impurity status and when she will have the presumptive status of ritual purity. As stated, there are no natural or fixed principles that can be followed in all cases, and the issue of how to deal with differences between one woman and the next, as well as the variations within each individual woman, occupies a significant portion of this tractate.

Another halakhic topic that has significant practical ramifications is with regard to blood stains. Many of the cases discussed in the tractate do not involve isolated blood, but rather blood that has been absorbed into clothing or found somewhere else. In most instances it is easy to verify the facts with regard to the source of a discovered blood stain and when it appeared. Yet, in many situations when blood is found absorbed in clothing or somewhere on the body, the time of its appearance and its origin are unclear. In such cases it might even be unknown whether the blood came from the body of a woman or from another source, such as an animal. Furthermore, even if it came from a woman, it may be uncertain whether it is uterine blood or blood from a wound found in the vaginal canal or from some other wound.

Tractate Nidda discusses the halakhic implications of all these aforementioned types of blood. It largely discusses an aspect that is still applicable nowadays, the prohibition of intercourse, and for that matter, all forms of physical intimacy with a menstruating woman. Apropos of this topic, it also discusses matters that are not relevant nowadays, specifically the study of ritual purity as it relates to the status of a menstruating woman.

There is one halakha that renders virtually obsolete a large proportion of the most basic halakhic concepts contained in this tractate. The Talmud refers to this halakha as the stringency that Jewish women accepted upon themselves, and it is considered by the authorities as the basic halakha. This stringency is that every woman who sees even the most minuscule amount of possible menstrual blood automatically assumes the ritual impurity status of a zava. In many cases there is no perceivable basis for this concern, but nevertheless it determines all the relevant halakhot. Due to this accepted custom, there is no longer any practical significance to many of the details and discussions contained in this tractate.

The tractate also includes lengthy discussions of the halakhot of childbirth. The halakhot that apply to a normal childbirth are stated explicitly in the Torah. Yet, there are many questions with regard to irregular occurrences, such as caesarean births and various types of miscarriages, including instances where the fetus is deformed to the point where it does not have a human form. Another matter that requires clarification is the stage of pregnancy when a miscarriage is considered a full-fledged birth. The analysis of these issues is important both with regard to establishing whether any ensuing blood is considered menstrual blood, and for determining the purity status of the mother.

Another detailed discussion in this tractate is the various stages that a child passes through on his or her way to adulthood. What are the external physical signs that indicate the stages of a developed youth, and which subsequent signs are indicative of adulthood? These definitions are important with regard to both the halakhot of menstruation as well as the obligation to observe mitzvot and the liability for punishment that come with adulthood.

Nidda is considered one of the more difficult tractates of the Talmud. There are several reasons for this. One is that a significant portion of its discussions is either connected to, or entirely focused on, the halakhot of ritual impurity. As far back as talmudic times, the halakhot of ritual impurity have been considered one of the most complex systems of Torah law. The Rambam writes in his introduction to Teharot that even if one were to review them many times, he would still be lacking in his clear understanding of these matters. This is partly because their basic principles cannot be logically deduced, which results in many discrete halakhot, each of which is apparently dictated by its own logic or internal rationale. Another difficulty in studying this tractate that obfuscates the basic reading of the text is that the Talmud often speaks in euphemistic terms, designed to mask material of a sexual or graphic nature. Metaphors, symbols, and analogies are often used for this purpose. Since the basic meaning of the words and the concepts in question is ambiguous, this can lead to difficulties in analyzing the text, both in terms of general ideas and with regard to the halakhic ramifications.

The vast majority of the tractate deals with the clarification of halakhic principles and how they may be applied. In addition, it also contains a certain amount of aggadic literature. In most cases the aggadic passages are closely related to the main topics of the tractate. Some are cited in order to help clarify ideas or situations, while others teach proper ethical behavior or delve into spiritual matters connected to the main discussion.

Tractate Nidda contains ten chapters. A single chapter might deal entirely with one topic, or a topic might span across more than one chapter. Likewise, there are chapters that focus on varied topics.

Chapter One discusses the point at which a menstruating woman transmits ritual impurity due to uncertainty. It also addresses the issue of which women are considered either temporarily or permanently pure due to their suspended menstruation.

Chapter Two deals with the ways in which a menstruating woman performs her self-examinations, as well as the various shades of blood that cause a woman to have the status of a menstruating woman.

The main topic of Chapter Three is miscarriages. The chapter defines what is considered to be a fully formed fetus and what is only an incomplete sac.

Chapter Four addresses two central topics: One is the halakhot of menstruation as they apply to Cuthean, Sadducee, and gentile women. The other is the menstruation or ziva status of a woman who is having difficulty giving birth and discharges blood for a substantial period of time.

Chapter Five continues with the previous topics, but its main focus is the stages at which girls and boys pass into adulthood.

Chapter Six further analyzes these topics, although it mostly contains a collection of varied halakhot and topics gathered together not due to their content, but due to their similar structure and style.

Chapter Seven deals with categories of ritual impurity for which wetness or dryness makes a difference. It also discusses the halakhot of impurity with regard to Cutheans.

Chapter Eight focuses on the halakhot of blood stains found on a woman's clothing or skin. It defines which stains cause impurity and which are treated leniently.

Chapter Nine discusses what to do when the origin of found blood is unknown. When is it assumed that the blood came from a certain woman and when can it be presumed that it came from other sources? In addition, the chapter explains how stains can be analyzed to determine if they are in fact blood or some other substance. This chapter also contains a discussion of the establishment of fixed menstrual cycles, whether they are based upon specific dates or upon particular physical phenomena.

Finally, Chapter Ten deals with a variety of topics, including bleeding from the torn hymen, examinations of various forms of ritual impurity where there is uncertainty as to the accuracy of the examination, blood of purity following childbirth, and the halakha of one who passes away in a state of ritual impurity. In addition, there is a discussion concerning a woman who engages in intercourse with her husband before she completes the full process required to attain ritual purity.