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Class Notes - Class #8

There are several more mitzvot in this series that prohibit certain sexual relations, and we will cover those in this class.

            Mitzvah #207 prohibits a man from having sex with a Jewish woman who is a niddah.  The author does not mention that this mitzvah prohibits sex by the female partner.  But Lev. 20:18 says that “both of them” are punishable when a man has sex with a woman who is a niddah, and Rambam clearly holds that both people are liable.  Another clarification: the author’s discussion makes it clear that the prohibition on sexual relations also includes a man having sex with a woman who is a zavah or a yoledet, although the author does not explicitly mention that or explain a source for those prohibitions.  The author covered the shoresh for this mitzvah when he discussed these categories in the context of tumah and taharah, and we discussed it then.

            This mitzvah d’oraira governs Jewish women, not non-Jewish women. It includes shifchah, a non-Jewish female slave owned by a Jew.  She is required to do certain mitzvot, and she becomes Jewish automatically if she is ever freed, so for this purpose she has the status of a Jew. (As we will see shortly, she is also has the status of non-Jew in some cases.)  There is a long history of masters taking sexual advantage of female slaves, and perhaps this rule puts some limit on that.  We will get a better understanding of the halachah that governs non-Jewish slaves later in our study.

The author says that d’rabanan, non-Jews, men and women, are considered like a zav or zavah for the purposes of tumah and taharah, so sex with a non-Jewish woman who is a niddah would be prohibited d’rabanan because she would be considered as a zavah.   He cites the Gemara for the proposition that there are four rabbinic prohibitions on a Jewish man having sex with a non-Jewish woman.  The clear implication is that there is no d’oraita prohibition.  (Things are a little different if the man is a cohen, but we will deal with that when we get to mitzvah #266.)

When a woman is a niddah, zavah or yoledet, Jewish men are prohibited from having sex with her.  The author’s first main theme in this mitzvah/essay is tracing the history of the changes in how this mitzvah was observed.  To follow his essay, we need to review when a woman is a niddah or a zavah. 

Niddah is a woman having normal menstrual flow.  When a woman sees bloody discharge that makes her a niddah, she waits a minimum of seven days or until the discharge stops, whichever is longer, then immerses on the night after the seventh day, and becomes t’horah.  The first time a woman sees bloody discharge she is considered a niddah, even if she is a tiny child.  If the woman never immerses in a mikvah after becoming a niddah, the woman remains t’meiah indefinitely.

A woman who sees bloody vaginal discharge in the eleven days after she has been a niddah is a zavah.  If she sees discharge for one or two days, the woman is a zavah k’tanah: she waits one day and, if there is no further discharge, she immerses in the mikvah and becomes t’horah.  If she sees discharge for three days or more, she is a zavah g’dolah:  when the discharge stops, she counts seven days without discharge, then immerses in the mikvah and becomes t’horah.  If she never immerses in a mikvah after becoming a zavah, the woman remains t’meiah indefinitely.

This was a complex rubric, and married Jewish women had to keep track of it in their everyday lives.  The author says the women did just what they should have done, and that when a woman says she did something that is relevant to these issues, she is believed.  His attitude toward how women related to this halachic rubric is revealing.  One might expect the author to be somewhat condescending toward the women, but he is not.  None of the changes in the way this area of halachah was practiced came about because the women were uncooperative. 

The author adds another aspect to this rubric.  Only certain colors of bloody discharge were considered blood that made a woman a niddah or zavah.  In close cases, rabbis would examine a sample of a woman’s discharge to see if the color was one of the five bloody colors that made the woman t’meiah.  In theory, only uterine blood makes the woman t’meiah.  The halachah was based on distinguishing uterine blood from blood from other sources by color.  The author explains that at some point, the rabbis decided they could not longer make that distinction.  The author does not say when that happened; he does say it was related to the rabbis losing confidence in their ability to do so during a period of hard times.  Thereafter, any red or black shade was considered blood that makes the woman t’meiah; discharges of other colors do not make the woman t’meiah.

Enter the law of unintended consequences.  Rabbi Yehudah haNasi made the next change.  He was the author of the Mishanh, and wrote about 130 years after the destruction of the Temple, so niddah, zavah, and yoledet were only relevant to sexual interactions, and were no longer relevant to tumah and taharah as it related to the Temple. 

The women were still keeping careful track of the differences between niddah and zavah, but there was no longer a way to tell whether any given bloody discharge did or did not make her t’meiah.  So there might be times when a woman considered herself t’meiah because of a discharge that did not really make her t’meiah.  That resulted in the following potential problem.  Let’s say a woman sees a bloody discharge.  She believes it makes her a niddah, so she waits seven days.  She stops seeing a discharge on day seven.  She immerses in a mikvah on the night after the seventh day, and she thinks she is t’horah.  But what she did not know was that the bloody discharge she saw on the first six days was not a discharge that would make her t’meiah, whereas the discharge she saw on the seventh day really was a discharge that would make her t’meiah.  In that case, she would have to wait an additional six days before immersing.  But she did not do that, because she assumed that all of the discharge was dam niddah.  The result is that she is still t’meiah after she immersed, she is not t’horah as she thinks she is.

And that error will compound.  Recall that the woman will be a zavah if she has a qualifying discharge in the eleven days after the end of her time as a niddah.  If she is mistaken about when she is a niddah, she will be mistaken about when she is a zavah.  Then, in the future, she might not be accurate about which status she falls into when she has a bloody discharge and she might follow the procedure for the wrong status.

Rabbi Yehudah legislated in an attempt to solve this problem.  If a woman saw blood for one or two days, she should wait six days with no discharge and then immerse in the mikvah.  If she saw blood for more than two days, she would wait for the discharge to end, count seven days without a discharge and then immerse in the mikvah.

 Let’s analyze how this regimen solves the problem.  If she sees blood for one or two days, that might be dam niddah, or it might be blood that makes her a zavah k’tanah, but two days of discharge is not enough to make her a zavah g’dolah.  If the blood was dam niddah, she would need to count a total of seven days before immersing in the mikvah; the two days of discharge plus six days without discharge is more than enough.  If the blood was dam zavah, she would be a zavah k’tanah, who has to wait one day before immersing.  Again, the six days without discharge is more than enough. Even if the first day was dam zavah and the second day was dam niddah, the one day of discharge plus the six days without discharge works.

If the woman had discharge for three days or more, she might be a niddah or she might be a zavah g’dolah.  If the blood was dam niddah, she would have to wait seven days and then immerse, assuming the discharge had stopped.  The three days of discharge plus seven days without discharge are more than enough. And if the discharge was dam zavah, she is following the rules for a zavah g’dolah, counting seven days after the discharge had stopped before immersing.  It appears Rabbi Yehudah had a fix for the problem.

            But this time the women were not satisfied.  They chose to treat all bloody discharge as if the discharge made the woman a zavah g’dolah even if a woman only saw discharge on one day.  The rabbis thought that change “good and necessary,” and so it went thereafter. It is hard to know why the women chose to make that change.  It certainly made the calculations easier, as the women no longer kept track of different kinds of status requiring different kinds of resolution.  But it cut down some on the time they were permitted to have sex.  It is hard to know why the rabbis found it good or necessary, and a little hard to imagine the husbands agreeing.  But, as the author says, the Gemara relates the story of these developments in many places.

            The author’s description of this historical process teaches us several things about how the author understood the development of halachic practice.  First, it shows that many things other than pure intellectual analysis influence the development of halachic practice.  This series of developments began because the rabbis lost some important halachic information, specifically how to distinguish the color of discharge that makes a woman t’meiah from the color of discharge that would leave the woman t’horah.  The rabbis were not infallible; they lost important halachic information.  The solution they formulated when that happened had unintended consequences.  When that problem came to light, Rabbi Yehudah haNasi proposed a solution, but the women who were supposed to follow that solution replaced it with a solution of their own.  Apparently, halachic practice develops as a dialogue between rabbis and the rest of the Jewish people.

            After describing that history, the author explains several other aspects of this mitzvah.  It seems to me he might be going into so much detail because he is taking the opportunity to explain these matters to his teen-aged son, as if he was thinking,  “As long as we are on this topic, we might as well get the entire awkward discussion out of the way.”  Note that the author’s presentation of this material is explanatory and straightforward.  He is not teaching intellectual skills in this essay, he is explaining how married people behave as governed by this mitzvah.  His description may not exactly match current common practice. We will not repeat all the details the author explains; rather we will just outline the topics he covers.

            First, the author deals with the question of how much discharge is enough to cause the woman to be a niddah/zavah.  D’oraita, any amount of discharge is enough, but only if the woman is aware that she is having a discharge.  D’rabanan, however, a stain of a qualifying color found in a place where it could reasonably be expected to be vaginal discharge counts even if the woman did not have any sensation of the discharge.  But there are exceptions if there is some other explanation for the stain, for example bleeding from a wound.

            Next, the author explains the procedure a woman goes through to become t’horah after she sees a bloody discharge.  If the woman saw discharge only one day, she would wait that day and the next, then do an internal examination and, if that showed no blood, begin to count the seven “clean” days.  If the woman saw discharge for two or three days, she would wait until the night after the discharge stopped, do an internal examination, and begin counting the seven clean days.  If she saw only a stain, but did not see any other discharge, she can do an internal exam on that day and begin counting the seven clean days that night.  The rule for this case is less stringent because the stain only makes her t’meiah d’rabanan. The woman continues to examine herself daily during the seven clean days, although if she missed an examination, as long as she remembered to examine herself at the very beginning and at the end of the last day of the seven clean days, the process is valid.  The author goes into detail about exactly how the woman does the required examinations.

            When the required examinations are successfully completed, the woman immerses in the mikvah.  Although a woman who is a zavah immerses in the mikvah during the day, now that women no longer distinguish niddah from zavah, d’rabanan women immerse at night.  The reason is given in the Gemara, “the attachment of the daughter.”  That is an obscure phrase that the author does not explain.  In extenuating circumstances she may immerse during the day on the last of the seven clean days, but sex is still forbidden until nightfall.

            The author explains extra restrictions between husband and wife on the days when she has reason to expect she will begin to menstruate.  The author also outlines extra restrictions the rabbis imposed on husband and wife when they are prohibited from having sex with each other.

            The punishments the author lists at the end of the essay should be clear and familiar by now.  The author does not mention that the woman is also punishable.  The author mentions that if a couple violates this mitzvah and a child is born from that union, the child is not considered a “mamzer.”  A mamzer is the child of certain forbidden sexual relations who ends up with very severe restrictions on who the mamzer can marry.  We will learn more about this institution late in out study.


Mitzvah #209 prohibits sex between two men.  The author explicitly says this prohibition applies to both the active and passive partner.  As usual, penetration defines the violation of this mitzvah d’oraita.  Here, we could use a more detailed definition of penetration.  We do not know whether penetration into any bodily organ violates this mitzvah.

The author includes two ideas by way of shoresh.  First, male homosexual sex involves destruction of semen, a potential source of human life, for no “fruitful” purpose.  Second, the author says this behavior is repulsive and loathsome.  These explanations may not seem entirely satisfying.  There are other permitted sexual relations that have no “fruitful” purpose, for example a man having sex with a pregnant woman.  As to the author’s second point, this behavior seems repulsive to some and not to others.  Note, though, that the author focuses on the behavior.  Homosexual sex between men is forbidden.  The men involved have no different status from any other men who do forbidden things. 

Also note that, in the context of this mitzvah, the author does not mention any prohibition on erotic behavior between women.  In mitzvah #188, the author cited the midrash halachah’s explanation of a verse that tells us not to behave the way the Canaanites and Egyptians behave.  (Lev. 18:3)  The midrash halalchah describes the behavior we are supposed to avoid:  “a man would marry a man, a woman would marry a woman, and a woman would marry two men.”  It is not clear exactly what behavior that statement describes, especially as it comes to two women marrying each other.  Nor is it clear is the midrash halachah is describing a prohibition d’oraita, a prohibition d’rabanan, or just describing behavior that is “not recommended.” 

Mostly in this essay the author deals with tangents. We will see the author taking on topics tangentially related to this entire series of mitzvot in the last few essays.  Here, first he deals with three different ways rabbis understand several interrelated verses.  Second, he explains who is punished when the violation of this mitzvah involves a child.  Third, he discusses this prohibition as it relates to non-Jews.

The author discusses how three different rabbinic authorities understand the source verse for this mitzvah in relation to other verses.  Consider the following verses:

  1. The source verse here, Lev. 18:22, says “Do not have sex with a man as with a woman….” We have seen that all of the source verses in this series of mitzvot have been addressed to men, and this is no exception. 
  2. Deut. 23:18 says, “There should not be a kadesh among the Jews….” We will see other possibilities, but a reasonable translation of kadesh is male prostitute.
  3. Deut. 7:3 says, “And do not marry them….” In context, this refers to the seven nations who lived in Israel when the Jews invaded and conquered.
  4. Deut. 7:4 says, “For she will turn your son away from following Me….”

Onkelos is a translation of the Pentateuch into Aramaic that dates from the second century C.E., much earlier than our author and his contemporaries.  Onkelos translates verse 2 as a prohibition on a Jewish man marrying a shifchah, a non-Jewish female slave.

Rambam disagrees with Onkelos’ translation.  According to Rambam, verse 2, about the kadesh, is just emphasizing the prohibition on male homosexual sex in our source verse, and has nothing to do with marrying a female slave.  Nor does verse 2, about the kadesh, add a prohibition on the passive partner in the homosexual relationship.  Rather, the word “nishkav” in verse 1 includes the active and the passive partner. Rambam relies on Rabbi Akiva’s opinion cited in Gemara Sanhedrin 54b to that effect.  Rambam apparently thinks there is no separate d’oraita prohibition on male prostitution.  Verse 2 only reinforces the prohibition in verse 1.

Ramban also disagrees with Onkelos.  According to Ramban, verse 2 does add a new prohibition; it prohibits a Jewish man from being a prostitute among Jews.  Since verse 2 says “among Jews,” there is no specific prohibition on non-Jewish male prostitutes, even if the prostitute sells his services to Jews. The prohibition on male homosexual sex would apply to that relationship, though.

There is one problem with this analysis: everyone agrees there is a Biblical prohibition on a Jewish man marrying a shifchah.  That works fine for Onkelos.  But Rambam and Ramban need a source for that prohibition. 

The author first tries using verse 3.  Maybe the “them” are non-Jewish female slaves.  But verse 3 is understood to prohibit marrying the Canaanites who lived in Israel when the Jews conquered it and who later became Jewish. The rest of the verse says, “Do not give your daughter to his son, or take his daughter for your son.”  Since such a marriage would be prohibited in any event, this verse must prohibit marriage even if the locals convert.  The verse is not available to prohibit marrying the non-Jewish female slave. 

Next the author tries the following verse, what we have called verse 4.  In context, that verse seems to be explaining the prohibition in verse 3 on marrying the locals even if they have converted.  But the Gemara uses it to extend the prohibition above to a non-Jewish female slave.  Actually, the shifchah is an ambiguous case.  She is currently not Jewish, but she will be Jewish is she is ever freed, and certain mitzvot that apply to Jews also apply to her. The rabbis use verse 4 to argue that, for the purpose of marriage, she should not be considered Jewish, since she might influence her Jewish husband based on her non-Jewish roots.  Therefore a Jewish man is prohibited from marrying her.

The second topic the author covers in this essay appears in his summary of the punishments.  Here, he considers how the punishments play out if one of the participants in the sexual encounter is a child. We will go through each case the author discusses to make sure we understand it.   We have mentioned earlier that sexual activity by young children, girls under the age of three and boys under the age of nine, is not considered sex at all.  All of the cases the author mentions assume witnesses and warning.

  1. If both participants in the sex prohibited by this mitzvah are adults the punishment is death by stoning. 
  2. If an adult man had sex with a boy under the age of nine years, neither is punishable d’oraita.  Since the boy is too young, d’oraita the mitzvah has not been broken.  D’rabanan, however, the adult gets makat mardut.  Apparently the rabbis prohibited this sex act.
  3. If an adult man had sex with a boy between the ages of nine and thirteen years, the adult is punishable with death by stoning.  As an adult he is completely responsible for his actions and, since the boy was over the age of nine, the sex act violates this mitzvah.  But the boy is not punishable d’oraita because, since he is not yet an adult, he cannot be held responsible for his improper behavior.  The author says the boy gets makat mardut, presumably to discourage this behavior in the future.

The author sums up some other topics related to punishment.  He mentions what happens if the sex that violates this mitzvah is done without witnesses and warning, or b’shogeg, and the results are exactly what we would expect.

 The author also discusses a man having sex with someone of ambiguous gender.  There are two types of people of ambiguous gender:  tumtum,” a person with no sexual characteristics of either a male or a female, and “androgynous,” a person with both male and female sexual characteristics.  If a man has sex with a tumtum, he has not violated this mitzvah because the tumtum does not have sexual characteristics of a man.  But that sex act is prohibited d’rabanan.  An androgynous does have male sexual characteristics, so if a man has sex with an androgynous who is the active partner, both of them have violated this mitzvah.   If a man has sex with an androgynous who is the passive partner, they have not violated a mitzvah d’oraita but they have violated a d’rabanan.  The author also mentions that an androgynous is permitted to marry a woman.

            Last, the author says the prohibitions on male homosexual sex, as well as the prohibitions on bestiality we will see next, apply to all people, not just Jews. The author considers the case of a non-Jewish slave, parallel to the shifchah we saw earlier.  A non-Jewish slave owned by a Jew has an intermediate status between being a non-Jew and being a Jew.  The slave is not Jewish, but will be Jewish if he is ever freed.  As we will see later, the slave is obligated in some mitzvot but not others.  Since the prohibition on male homosexual sex applies to Jews and to non-Jews, it is clear that the prohibition also applies to non-Jewish slaves.  But the author mentions it here because the incest prohibitions we saw earlier do not apply to the slave.  When someone converts to be Jewish, the halachah considers the convert a new person.  The person is no longer considered related to his or her blood relatives, so the prohibitions on incest do not apply.  (The rabbis step in and prohibit them, though.)  Even though the incest prohibitions do not apply to the slave, the prohibition on male homosexual sex and the prohibitions on bestiality do apply, since they apply to Jews and to non-Jews.


Mitzvot #210 and 211 prohibit bestiality, #210 by men and #211 by women.  The author discusses the basics about these mitzvot, and then discusses several tangential topics related to the entire series of mitzvot about forbidden sex.

            The source verse here, Lev. 18:23, says explicitly that a man should not have sex with an animal and that a woman should not have sex with an animal.  The author explains why Rambam counts these two as separate mitzvot.  The author mentions that we could not derive a prohibition on women having sex with animals if we only had the prohibition on men having sex with animals, but even so Rambam might have understood the two parts of the verse as two aspects of the same mitzvah.  But the Mishnah lists cases that are potentially punishable by karet, that that list has separate items for male and female bestiality.  Thus, Rambam counts them as separate mitzvot.

            The shoresh of this mitzvah relates to the phrase that appears several times in the creation stories at the beginning of Genesis, where God says living things He creates should reproduce “after its own kind.”  To further that end, we have several mitzvot restricting our doing things involving mixing species for the purpose of procreation.  Another example is the prohibition on certain forms of grafting plants. 

            When these mitzvot are violated, the person involved is punishable following the rules we have already learned.  The animal is also put to death by stoning.  The author explains that the animal is killed to avoid having people continue to focus on the bestiality when they see the animal.  So the author explains the punishment of the person involved in various cases of bestiality, and also explains whether the animal is killed.  Again, let’s make sure we understand each case the author discusses.

1.      If the person is an adult and acts b’mazid with witnesses and warning, the person is punished with death by stoning and the animal is killed.  If the person acted b’mazid but without witnesses and warning, he or she is subject to karet.  If the person acted b’shogeg, the person is obligated to bring a hattat.  The author says that in the case of shogeg the animal is not killed.  A man is an adult if he has reached the age of 13; a girl is an adult when she has reached the age of 12.

2.      If the person is a boy older that nine, or a girl older than three, the child is not punishable d’oraita because the child is too young to be held responsible for his or her actions.  The author says the child should be admonished.  The author does not say how the child is admonished.  But, since the boy was over nine years old, or the girl was over three years old, the sex act is considered a sex act, and so the animal is killed.

3.      If the person is a boy under the age of nine or a girl under the age of three, neither the boy nor the animal is punishable.  Sexual activity by children that young is just not considered sexual activity.


The author chooses mitzvah #211 to mention several other factoids about punishments.   Some of these are more applicable to the prior prohibitions in this series of mitzvot than they are to bestiality.  He says that there can be no punishment of the death penalty or of karet unless there is a Biblical source.  The source for the specific type of death penalty can be in the Torah or from the oral law.  The author also mentions that when the forbidden sex is between two people and one of the people was asleep, the sleeping person is not liable to punishment at all, even if the person had some level of sexual pleasure from the act.  The sleeping participant has not violated the prohibition b’shogeg; the person was not acting at all, and not even fully conscious that the act was being done. 

            The author provides more information on the role of witnesses in cases of forbidden sex.  As we mentioned earlier, the witnesses do not actually have to see the penetration, they only have to see the two participants in position.  In incest cases, the court does not require proof of the relationship between the two parties if the people have acted in public in ways that lead others to believe they are related to each other in a specific way.  Rather, there is a presumption that people who hold themselves out as related are in fact related, and they are punishable without further proof.

            Finally, the author summarizes the applicability of these mitzvot to non-Jews, to non-Jewish slaves, and to people who have converted to Judaism.  Only some of the prohibitions apply to non-Jews.  Specifically, a non-Jewish man is forbidden to have sex with his mother, his father’s wife, his sister from the same mother, someone else’s wife, other men, and animals.  We saw earlier that the non-Jewish man is also forbidden to have sex with his father, although that is apparently based on the prohibition on male homosexual sex.  The author does not mention any of these mitzvot applying to non-Jewish women, although if bestiality is prohibited for non-Jewish men it seems reasonable to assume that it is also forbidden for non-Jewish women.  We wondered about how the author dealt with the applicability of these mitzvot to the Jewish female sexual partners; the same puzzle applies to the author’s discussion of non-Jews.

            As we said before, a non-Jewish slave owned by a Jew has an intermediate status between Jew and non-Jew.  The slave will become Jewish if he or she is ever freed, but the slave is not Jewish yet.  The slave is required to avoid all behavior prohibited by negative mitzvot.   A convert is considered as an entirely new person, without any blood relatives.  If the slave has no blood relatives, the incest prohibitions cannot apply.  But some of the sexual acts prohibited by this series of mitzvot that are not incest, and those prohibitions do apply:  male homosexual sex, bestiality, sex with a married woman and sex with a niddah. 

The prohibition of niddah on this list is a bit of a surprise.  The rabbis interpret Lev. 15:19, discussing niddah as an aspect of tumah in the Temple service sense, to include Jewish and non-Jewish women and shifchaot.  The author says sex with the shifchah who is a niddah is prohibited because Torah prohibitions on Jews apply to the shifchah.  It is possible to understand this assertion to mean that a woman who is a niddah is prohibited to have sex.  The author did not mention that in mitzvah #207.  That gives us another piece of evidence about how our author is handling the applicability of all of these mitzvot to the female partner.  Here, the author says something that implies a woman who is a niddah is forbidden to have sex, even though he did not mention that in the relevant mitzvah.        

The author cites the midrash halachah in support of the proposition that halachah does not recognize the relatives of a non-Jewish slave.   Abraham, on his way to the “sacrifice” of Isaac, tells his two slaves to stay back  im ha hamor,” “with the donkey.”  (Gen. 22:5.)  The midrash halachah suggests changing the vowel to replace the word “im,” “with,” with the word “am,” “ nation.”  Thus, the verse would mean that it is as if Abraham’s two servants are animals rather than people, and that therefore we cannot assume we know who they have had sex with.  This is a disturbing midrash for several reasons.  First, even with that reinterpretation of the verse, it is hard to see how the words of the verse lead to the halachic conclusion.  And, of course, the midrash is dramatically insulting.  There are many streams of thought in halalchic literature, but our author does not seem to be fond of the dramatically insulting streams.  It seems strange to me that he cites this midrash halachah, as the tone seems out of character for him, and he could just have told us what the rule is without giving its source.

            Last the author deals with the impact of these mitzvot on converts, a category that includes freed non-Jewish slaves.  The rubric d’oraita is the same as for the non-Jew who is still a slave:  male homosexual sex, niddah and bestiality are forbidden.  D’oraita, the convert could have sex with any of his blood relatives.  But the rabbis did not want to create the impression that when someone converts, he gets to do things generally accepted to be immoral that he was not allowed to do as a non-Jew.  They prohibited the convert from having sex with any of his female relatives through his mother, as it is generally clear who someone’s mother is.  Sex with women who are related to him through his father are not forbidden.  And sex prohibited to Jews d’rabanan is permitted for them.

            Last, the author considers what happens if a man converts and some of his blood relatives also convert.  (The same rubric applies to freed slaves.)  Here again, d’rabanan, sex with relatives on the mother’s side is prohibited whereas sex with relatives on the father’s side is not.  That matches the rule that halachah recognizes blood relatives for non-Jews through the mother’s line but not through the father’s line.  So a male convert is prohibited from having sex with his mother, having sex with his sister from the same mother, or from marrying two sisters at the same time if the sisters share a mother.  But he is permitted to marry his daughter (if she also converted,) and his son’s wife.  If before he converted, he was married to someone he was prohibited from having sex with while he was still a non-Jew, for example his mother, and then he and his mother converted, d’oraita they would be permitted to marry as Jews.  But d’rabanan they are forced to dissolve the marriage, lest it look like the process of conversion allows them to do something that would have been immoral before then converted.


Which relationships are missing from this list that we might have thought should be here?  The closest blood relatives who may marry and have sex with each other are first cousins.  We already discussed sexual activity between two women.  We have not seen a prohibition on two unrelated Jewish adults having sex, at least assuming the woman is not a niddah, zavah or yoledet.  In mitzvah #207, the author told us there is a prohibition on a Jewish man having sex with a non-Jewish woman, but that prohibition is d’rabanan not d’oraita. The author did not mention any prohibition on a Jewish woman having sex with a non-Jewish man. There is no prohibition on a man having sex with his son, although that would be prohibited as male homosexual sex.  We have not seen a specific prohibition on an adult having sex with a child, and we have not seen any discussion that distinguishes consensual sex from coerced sex.  It seems that the author is assuming all the sexual relations he discussed in this series of mitzvot were consensual. We have some other mitzvot coming later in our study that prohibit other sexual relations.  We will have to see whether we get more information on these open questions.