1) THE DISCUSSIONS THAT OCCURRED "ON THAT DAY"
QUESTION: The Mishnah (27b) cites four Halachic discussions that occurred "Bo va'Yom" ("on that [same] day" -- the day on which Raban Gamliel was deposed from his position as Nasi and Rebbi Elazar ben Azaryah was appointed in his place). These discussions involve various Halachos and Agados which the Gemara elucidates at length.
The first discussion involves a dispute about whether food that is Chulin can become Tamei with Shelishi l'Tum'ah.
The second is a dispute about whether the Isur of Techumin is mid'Oraisa or mid'Rabanan.
The third is a dispute about how the Jewish people sang the Shirah at the splitting of the Sea.
The fourth is a dispute about whether Iyov served Hash-m out of love or out of fear.
None of these discussions seem to be related to each other, or to the beginning of the Mishnah which discusses the law that the Sotah is prohibited from remaining with her husband and from marrying her adulterer.
RASHI on the Mishnah (end of DH Bo va'Yom) explains that the disputes about the source for the prohibition and punishment for the adulterer also occurred on that day, the day on which Rebbi Eliezer ben Azaryah replaced Raban Gamliel as Nasi. This is why the Mishnah digresses to discuss the other arguments that were discussed on that day.
Why, though, does the Mishnah choose these specific discussions? An entire Masechta discusses the Halachic discussions which occurred on the day that Rebbi Elazar ben Azaryah became Nasi: Maseches Eduyos. The Mishnah here could have cited any of the Mishnayos in Eduyos simply because the discussions occurred on the same day. Apparently, the Mishnah here records only a certain type of Halachah that was discussed on the day, a Halachah which is similar in some way to the discussion of the Sotah's prohibition to the adulterer (the subject of Maseches Sotah). In what way are these four specific discussions related to the discussion about the Sotah's prohibition to the adulterer?
ANSWER: To understand how these four discussions are related to the central topic of the Mishnah (the Sotah's prohibition to the adulterer), one first must examine why that topic itself was discussed on the day on which Rebbi Elazar ben Azaryah became Nasi. Apparently, the prohibition to the adulterer was discussed on that day as a reaction to the events that occurred: Raban Gamliel harshly reprimanded Rebbi Yehoshua for his dissenting views, the Chachamim objected to Raban Gamliel's treatment of Rebbi Yehoshua and deposed him from the Nesi'us, and they appointed Rebbi Elazar ben Azaryah in his place. The other discussions in the Mishnah were also raised as a reaction to the events of that day, and that is why the Mishnah records these specific arguments together. In what way were these discussions reactions to the events of that day?
(a) The dispute about the source for the Sotah's prohibition to the adulterer was discussed on that day in order to strengthen the people's caution in observing the Torah's prohibition against coveting another man's wife.
The Gemara in Berachos (35b) explains that the expressions "father" and "mother" are appropriate references to the relationship between Hash-m ("Father") and the Jewish people ("Keneses Yisrael"). In eras in which the Jewish people have no king, the Nasi serves in lieu of the king (as the Gemara in Sanhedrin (5a) interprets the verse, "Lo Yasur Shevet mi'Yehudah," Bereishis 49:10). The king, or Nasi, reflects the power of Hash-m's dominion (Berachos 58a). The people's willingness to subject themselves to the Nasi represents their willingness to subjugate themselves to Hash-m. The Chachamim were concerned that when the people saw that the Nasi could simply be deposed and someone else appointed to rule in his place, their sense of loyalty to their own spouses might be compromised. Therefore, the Chachamim sought to strengthen the people's awareness of the Isur by impressing upon them the consequences of the sin.
A precedent for this reaction may be found in the revolt of Korach. The Gemara (Moed Katan 18b) relates that all of the members of Korach's group warned (with Kinuy) their wives not to seclude themselves with Moshe Rabeinu. Why did they suspect Moshe Rabeinu of being an adulterer? Their claim was that every member of the Jewish people has a direct relationship with Hash-m because of each individual's lofty level (Bamidbar 16:3), and therefore they do not need Moshe Rabeinu to be their leader. They claimed that by trying to rule over the Jewish people, Moshe Rabeinu was committing an act of "adultery," so to speak, by taking Keneses Yisrael away from Hash-m to be a wife for himself. That was the message they communicated when they told their wives not to seclude themselves with Moshe Rabeinu.
(b) The Mishnah records Rebbi Akiva's rulings that Chulin can become a Shelishi l'Tum'ah and that the law of Techumin is mid'Oraisa. Rebbi Akiva always attempted to strengthen the authority of the Chachamim in order to refute the Tzedukim. The Gemara in Eruvin (21b) relates that Rebbi Akiva risked his life in order to strengthen the enactments of the Rabanan (such as the Takanah of Netilas Yadayim which, together with the Takanah of Eruvei Techumin, is one of the earliest enactments of the Rabanan, instituted by Shlomo ha'Melech).
When the authority of the Rabanan, as represented by the Nasi, was weakened, Rebbi Akiva was concerned that the people would treat lightly the Takanos d'Rabanan that they found difficult to accept. This fear was especially well-founded because of the change of policy in the Beis ha'Midrash (Berachos 28a). In the times of Raban Gamliel, only proven Torah scholars were allowed to enter and rule on Halachic matters. When Raban Gamliel was deposed, the policy was changed to permit anyone to join the discussion in the Beis ha'Midrash (potentially even Tzedukim). As the Mishnah here says, Raban Yochanan ben Zakai already announced that he was afraid that a later generation would rescind his ruling that Terumah becomes Pasul as a Shelishi because it was so difficult for the people to observe and his proof (the Kal v'Chomer) was tenuous. In order to prevent this from occurring, Rebbi Akiva pronounced that not only does Terumah become Tamei as a Shelishi, but even Chulin can become a Shelishi mid'Oraisa. In this way, he assured that no one would have the temerity to argue that a Shelishi is Tahor even with regard to Terumah.
(c) Just as Rebbi Akiva saw it necessary to strengthen the authority of the Chachamim with regard to Netilas Yadayim (Eruvin 21b), he saw it necessary to strengthen their authority with regard to the Isur of Techumin. When the Nasi's authority was challenged, rabbinical authority in general was challenged, and Rebbi Akiva was afraid that the people would challenge the Isur of Techumin. In order to strengthen its significance in their eyes, he asserted that the Isur of Techumin is not merely a Takanah d'Rabanan but rather it is an Isur mid'Oraisa. (According to Rebbi Akiva, when the Gemara in Eruvin says that Shlomo ha'Melech instituted ("Tiken") the laws of Techumin, it means that he was "Darash v'Hiskin" -- he publicly taught the Isur d'Oraisa; see Rosh Hashanah 30b.)
(d) Rebbi Akiva was afraid that the unseating of Raban Gamliel would prompt a Korach-type rebellion against the Nesi'us in general, with the people proclaiming that they are great enough to lead themselves and need no Nasi to rule over them. Therefore, Rebbi Akiva taught that even when Moshe Rabeinu and the Jewish people sang the Shirah at Keri'as Yam Suf, the Jewish people followed Moshe Rabeinu's lead and merely answered after Moshe Rabeinu. They let him lead them even though every one of them was elevated to the level of a Navi; they nevertheless realized the necessity of having a leader. Rebbi Nechemyah went even further and said that although the Jewish people were elevated to the same level of prophecy as Moshe Rabeinu when it came to choosing the words of the Shirah (see Rashi 30b, DH k'Sofer), nevertheless they did not feel that it was proper to begin the Shirah until Moshe Rabeinu led them and started the Shirah. (See YOSEF DA'AS in the name of the SHEM MI'SHMUEL, Parshas Beha'aloscha.)
(e) The objective of Rebbi Yehoshua ben Hurkenos' statement in the Mishnah was to strengthen the attitude of Rebbi Yehoshua and of the new Nasi, Rebbi Elazar ben Azaryah, towards Yir'as Shamayim and Avodas Hash-m, in contrast to the attitude of Raban Gamliel towards those matters. Why did Raban Gamliel not grant admission into the Beis ha'Midrash to any person who was not a proven Talmid Chacham? The Acharonim explain that Raban Gamliel was a disciple of Beis Shamai in several matters (see Beitzah 22b). Shamai was of the view that a person should serve Hash-m only with pure intentions. For this reason, he refused to accept the potential Gerim who sought to convert for ulterior motives (Shabbos 31a). However, as a result of this view, Shamai had less students than Hillel, who accepted everyone. Nevertheless, the students of Shamai were on a higher level of Torah scholarship than the students of Hillel, because of their purity of intention (see Yevamos 14a and Tosfos there, DH Rebbi Yehoshua). Rebbi Yehoshua, the Tana who argued with Raban Gamliel in Berachos, was a follower of Hillel's policy that everyone should be allowed into the Beis ha'Midrash. That is why -- after Raban Gamliel was dismissed -- they allowed everyone to enter. The difference in attitude towards learning reflected a difference in attitude towards serving Hash-m. Shamai's approach was to serve Hash-m through Yir'ah, and not to approach Hash-m until one is certain that he has purged himself of any impurities. Hillel's attitude was to serve Hash-m through love, and thus he encouraged an attitude of love and warmth between the Nasi and the people, in contrast to the approach of Raban Gamliel who encouraged an attitude of distance between the Nasi and the people. (See Avos 1:12, where Hillel says, "Be of the Talmidim of Aharon -- love peace and pursue peace.") The Mishnah quotes Rebbi Yehoshua ben Hurkenos' pronouncement that serving Hash-m out of love is a much higher level than serving Hash-m out of fear, and that the reason why Iyov received such great reward was because he served Hash-m out of love. This statement was a display of his approval for the new Nesi'us.

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