The Gemara begins by recounting an interaction between Rabbi Nahum and Rabbi Abahu. As they walked, Rabbi Nahum repeatedly posed questions on various halachic topics to Rabbi Abahu. One such question concerned the halachic ruling when a Mishnah presents a dispute (machloket) followed by an anonymous statement (stam). Rabbi Abahu replied that the halacha follows the stam, as previously learned.
Rabbi Nahum then asked: What if the order is reversed, with the stam appearing first, followed by a machloket? Rabbi Abahu responded that in such a case, the halacha does not follow the stam. This applies when a stam Mishnah is presented, and then a machloket follows. Rabbi Nahum further inquired: What if there is an anonymous Mishnah (stam Mishnah), but a machloket is found in a Baraita? Rabbi Abahu stated that we follow the stam Mishnah and disregard the machloket in the Baraita.
The discussion continued: What if there is a machloket in the Mishnah, followed by a stam in a Baraita? Normally, if this were within Mishnayot, a machloket followed by a stam would mean the stam is authoritative. However, Rabbi Abahu explained that if Rabbi (the redactor of the Mishnah) chose to record a machloket in the Mishnah, it implies that he did not intend for a definitive anonymous ruling to be established on that matter. If Rabbi had wanted to present a stam, he would have done so in the Mishnah itself. The fact that he wrote a machloket means that we follow the Mishnah's machloket over the Baraita's stam. Therefore, the Baraita's stam is not binding.
Rabbi Nahum challenged this by presenting a case where a machloket in the Mishnah is followed by a stam in a Baraita, yet we follow the Baraita. This case involves a comb for flax (masrek shel pishtan). The Mishnah states that if some of its teeth break off, leaving only two, the comb is ritually impure (tameh) because it remains functional. However, if only one tooth remains, it is ritually pure (tahor) because it is no longer functional. Each individual tooth that breaks off is considered functional and therefore tameh, as it can be used as a hanger or for cleaning a lamp wick.
The Mishnah then discusses a comb for wool (masrek shel tzemmer). If its teeth fall out in an alternating pattern (every other tooth), it is tahor because it is no longer functional. But if three teeth remain in a row, it is tameh because it is functional. An exception is made if one of the three remaining teeth is the thick, last peg, which is not suitable for combing; in this instance, it remains tahor. If two teeth break off and are used as tweezers, they are tameh. If one tooth breaks off and is designated for cleaning a lamp or hanging vessels, it is tameh.
The Gemara explains that the difference between the flax comb and the wool comb regarding the need for designation will be analyzed later. This is the ruling of the Mishnah. We referred to diagrams to visualize the comb and its teeth configurations.
The Gemara then states that there is a tradition (kayma lan) that we do not follow this Mishnah. Why? Because a Baraita disputes it. This presents a contradiction to Rabbi Abahu's rule: a stam Mishnah followed by a machloket in a Baraita should lead us to follow the Mishnah. Yet, here, we reject the Mishnah in favor of the Baraita, which contains a machloket. How can this be?
The Gemara resolves this by stating that Rabbi Yochanan and Reish Lakish both declared that this particular Mishnah is not accurate (zu einam Mishnah). Therefore, it is not a valid Mishnah, and its rulings are rejected. This allows the Baraita to become the primary source for the halacha.
The Gemara then explores why this Mishnah is considered invalid. One reason suggested is an internal contradiction: The Mishnah implies that two teeth in a row on a wool comb make it tameh, but later states that only three teeth in a row make it tameh, implying two teeth would be tahor. This is a contradiction between the beginning (reisha) and the end (seifa) of the Mishnah.
The Gemara refutes this challenge by offering two possible resolutions: 1. A distinction can be made between teeth located near the handle (gavyata) and those on the side (baryata). Two teeth near the handle might be functional, making the comb tameh, while two teeth on the side might not be, making it tahor. 2. Alternatively, the wool comb has two rows of teeth: an outer row (chitzonot) and an inner row (penimiyot). The outer row is primary for combing. Thus, three teeth are needed in the outer row for the comb to be tameh, while two teeth in the inner row might be sufficient.
Since these answers resolve the internal contradiction, the Gemara seeks another reason to invalidate the Mishnah. The next challenge arises from a discrepancy between the flax comb and the wool comb: For the flax comb, a detached tooth is automatically tameh because it is functional, without needing explicit designation. For the wool comb, however, a detached tooth is only tameh if it is specifically designated for a function. Why the difference?
The Gemara again offers two resolutions: 1. The difference depends on whether the tooth detached with a piece of its base (katayu) or without it (lo katayu). If it detached with its base, it has a "handle" and is automatically functional. If not, it requires designation. 2. Alternatively, the difference depends on the type of tooth: a small, narrow tooth (katinta) requires designation, while a thick, end tooth (alimta) is easily handled and automatically functional.
Since these challenges to the Mishnah's viability are resolved, the Gemara concludes that the Mishnah is rejected for a different reason: At its end, the Mishnah explicitly mentions "the words of Rabbi Shimon." This means it is not a stam Mishnah (anonymous and authoritative) but rather attributed to a specific sage. The rule that a stam Mishnah overrides a machloket in a Baraita only applies to truly anonymous Mishnayot. Since this Mishnah is not anonymous, we are not bound to follow it over a Baraita, even one with a machloket.
The Gemara then transitions to a new topic, discussing the laws of waiting periods before marriage. Rabbi Chiya bar Abin sent a question regarding the rule of waiting three months (shlosha chodashim) for a woman to ensure she is not pregnant before remarrying. This waiting period is called havchana. He noted that rabbis were lenient regarding engagement (Erusin), allowing it within the three-month period, specifically after a majority of the first month, the full second month, and a majority of the third month (approximately 62 days). This leniency for Erusin is because a woman cannot become pregnant during engagement.
Ameimar, however, had a different ruling: he allowed Erusin on the 90th day itself, not requiring a full 90 days to pass. This was also a leniency regarding Erusin. Rav Ashi challenged Ameimar, citing Rav Achul, who stated that the 90 days must be full, not including the day of death or the day of Erusin (meaning 92 days in total). How could Ameimar allow Erusin on the 90th day?
The Gemara clarifies that Rav Achul's strict ruling of "full days" applied to the 24-month waiting period for a nursing woman before remarriage, not the three-month havchana period. However, the Gemara then brings a counter-proof: A man made an engagement feast (seudat Erusin) on the 90th day, and Rabbah cancelled it, implying that the 90 days must be full. The Gemara answers that Rabbah's cancellation was for a marriage feast (seudat Nisuin), not an engagement feast. For actual marriage (Nisuin), which can lead to pregnancy, the Sages were stricter, requiring a full 90 days. Therefore, Ameimar's leniency for Erusin on the 90th day remains valid.
The final halachic conclusion is that for the 24-month nursing period, a full 24 months are required, not including the day of birth or engagement. Similarly, for the three-month havchana period, a full three months are required, not including the day of the first husband's death or the day of the second engagement. This applies even to Erusin, as a stringency.
The Gemara then returns to a Mishnah presenting a dispute between Rabbi Yehuda and Rabbi Yose regarding the three-month waiting period. Rabbi Yehuda states that he does not enact preventative decrees (gezerot). Therefore, if a woman was married (nesuah) and then divorced, she needs to wait three months before remarrying (Nisuin) due to havchana. However, if she was only engaged (arusa) and then divorced, she can immediately engage again (Erusin) or marry (Nisuin) because she could not have become pregnant from the engagement. Similarly, if she was married and then divorced, she can immediately become engaged to another man (Erusin), as engagement itself does not lead to pregnancy. Rabbi Yehuda holds of havchana but not of extending the decree from Nisuin to Erusin or vice-versa where havchana is not an issue.
Rabbi Yose, in the Mishnah, states that "all women" (kol hanashim) can engage or marry without concern, implying he does not make such decrees, but he specifically argues regarding a widow (almana). For a widow, he says she cannot remarry immediately due to the mourning period (avelut) for her deceased husband, which typically lasts 30 days. He introduces the issue of avelut into the discussion.
The Gemara analyzes Rabbi Yose's position regarding the widow. If Rabbi Yose argues that a widow cannot engage for 30 days due to avelut, the Gemara challenges this. It cites a ruling regarding the week of Tisha B'Av: during that week, it is forbidden to launder clothes, but it is permissible to engage (Erusin). This implies that where laundering is forbidden, engagement is permitted. By extension, in the 30 days of avelut, where laundering is permitted, engagement should certainly be permitted. So why does Rabbi Yose prohibit a widow from engaging for 30 days?
The Gemara clarifies the source for this comparison: a Baraita states that before the week of Tisha B'Av, one should minimize business transactions, but Erusin is permitted. This means that in a situation where business transactions are restricted, Erusin is still allowed. The Gemara initially misinterprets the Baraita's "before this time" as referring to the week of Tisha B'Av itself. However, it corrects itself: "before this time" refers to the period before the week of Tisha B'Av. During the week of Tisha B'Av, both laundering and Erusin are forbidden. Therefore, the comparison (kal v'chomer) that Erusin is permitted where laundering is forbidden no longer holds, removing the challenge against Rabbi Yose.
Rava then offers an alternative challenge to Rabbi Yose, even if the Baraita refers to the period before the week of Tisha B'Av. During that time, business transactions are minimized, but Erusin is permitted. If so, then in the 30 days of avelut, where business transactions are permitted, Erusin should certainly be permitted. So Rabbi Yose's prohibition on a widow engaging for 30 days is still problematic.
The Gemara resolves this by reinterpreting Rabbi Yose's statement in the Mishnah. Instead of reading "all women can engage," it should be read as "all women can marry (Nisuin)." According to this interpretation, Rabbi Yose is lenient regarding havchana, asserting that women can marry immediately without the three-month wait, as he does not make the decree. However, he makes an exception for a widow, who cannot marry (Nisuin) within 30 days due to avelut. He is not prohibiting Erusin for a widow, only Nisuin, which is a greater celebration (simcha) and thus forbidden during mourning.
This interpretation means Rabbi Yose fundamentally disputes Rabbi Yehuda on the principle of havchana itself, not just the decrees. Rabbi Yehuda accepts havchana but rejects the decrees, while Rabbi Yose rejects havchana entirely, allowing immediate Nisuin, except for the widow's Nisuin due to avelut. The Gemara notes that even Rabbi Yehuda would agree that a widow cannot marry within 30 days due to avelut, so Rabbi Yose's unique contribution is his leniency regarding havchana for all other women.
The Gemara then considers another interpretation of the Mishnah, suggesting that Rabbi Yose does hold of havchana and agrees with Rabbi Yehuda on not making decrees (e.g., allowing an arusa to marry immediately). However, his distinctive ruling is that a widow who was only engaged (arusa) cannot marry (Nisuin) within 30 days due to avelut. This implies that even an arusa who becomes a widow has a mourning period.
The Gemara immediately challenges this: If an arusa has a mourning period, then Rabbi Yose's position is identical to Rabbi Yehuda's regarding the arusa marrying, meaning there is no dispute. Furthermore, the Gemara asks if a woman who was only engaged (arusa) has a mourning period. It proves from a Baraita that an arusa does not have the laws of mourning for her deceased fiancé (e.g., she is not an onenet, a Kohen is not defiled for her, she is not obligated to bury him, and she does not inherit him). This definitively rejects the interpretation that an arusa has avelut. Therefore, the entire premise for this interpretation of Rabbi Yose's view on the widow is invalid.
The Gemara reverts to the first interpretation: Rabbi Yose does not hold of havchana at all. He permits all women to marry immediately, even Nisuin to Nisuin, without the three-month wait. His exception for the widow applies only to Nisuin (marriage), not Erusin (engagement), because Nisuin is a major celebration and is therefore prohibited during the 30-day avelut period for a married widow (nesuah almana). Everyone agrees that a married widow must observe 30 days of mourning before remarrying.
The Gemara then re-examines the initial challenge against Rabbi Yose's statement about the widow not being able to engage (Erusin) immediately. The challenge was based on the kal v'chomer from the laws of Tisha B'Av: if during the week before Tisha B'Av, business transactions are restricted but Erusin is permitted, then in the 30 days of avelut, where business transactions are permitted, Erusin should certainly be permitted. The Gemara now states that the premise of this kal v'chomer is flawed because there is a dispute among the Sages (Tannaim) regarding Erusin during the nine days before Tisha B'Av. Some hold that during these nine days, both business transactions and Erusin are forbidden. If Rabbi Yose follows this opinion, then the kal v'chomer does not apply, and his ruling that a widow cannot engage for 30 days is consistent.
However, the Gemara questions whether "Erusin is forbidden" in the context of Tisha B'Av truly means the act of engagement itself is forbidden, or merely the celebratory feast associated with it. If it only refers to the feast, then the act of engagement itself might still be permitted, bringing back the kal v'chomer. The Gemara clarifies that if "Nisuin is forbidden" means the marriage itself is forbidden (as marriage is inherently a celebration), then "Erusin is forbidden" should also mean the engagement itself is forbidden, not just the feast. However, the Gemara concludes that a distinction can be made: Nisuin is a major celebration, so the marriage itself is forbidden. Erusin, however, is not inherently a celebration, only its feast is. Therefore, the act of Erusin might be permitted during the nine days, even if the feast is not.
This brings the discussion back to the original kal v'chomer: if Erusin is permitted where business is restricted (before Tisha B'Av), then it should certainly be permitted where business is allowed (during avelut). Therefore, Rabbi Yose's prohibition on a widow engaging for 30 days remains problematic.
The Gemara's final answer is that there is no comparison between the laws of Tisha B'Av and the laws of individual mourning (avelut yachid). Tisha B'Av is an "old mourning" (avelut yeshana) for a past event, and its rules are distinct. Furthermore, Tisha B'Av is a "public mourning" (avelut rabim), which is considered less stringent than individual mourning because collective mourning offers a degree of consolation. Therefore, leniencies allowed during Tisha B'Av do not imply similar leniencies for fresh, individual mourning. According to this, Rabbi Yose in the Mishnah states that all married women (nesuot) can engage (Erusin) immediately, as he holds of havchana but not of decrees (e.g., from Nisuin to Erusin). However, he is stringent regarding a widow who was married (nesuah almana), prohibiting her from engaging for 30 days due to avelut. He distinguishes between the laws of Tisha B'Av and individual mourning, asserting that the leniencies of Tisha B'Av do not apply to individual avelut. This means Rabbi Yose argues with Rabbi Yehuda regarding the permissibility of Erusin for a married widow during the 30-day mourning period, with Rabbi Yehuda permitting it and Rabbi Yose prohibiting it. The Gemara concludes by reiterating that the first interpretation, where Rabbi Yose does not hold of havchana at all, also remains a valid way to understand the Mishnah.