1) VISITING ONE'S REBBI DURING THE FESTIVAL
QUESTION: A Beraisa relates that Rebbi Ila'i once went to greet his Rebbi, Rebbi Eliezer, during Sukos. Rebbi Eliezer asked him why he left his home when the Torah requires that one stay home and rejoice with one's wife during the festival.
The Gemara asks that the requirement to stay home with one's wife during the festival conflicts with the requirement to travel to one's Rebbi on the festival. Rebbi Yitzchak says that the requirement to visit one's Rebbi is learned from the words of the Shunamite woman's husband, who asked his wife, "Why are you going to him (the prophet Elisha) today? Today is not Rosh Chodesh and not Shabbos" (Melachim II 4:23). This verse teaches the requirement to visit one's Rebbi on Rosh Chodesh and Shabbos. Accordingly, Rebbi Ila'i was justified in going to visit Rebbi Eliezer during Sukos.
What is the Gemara's question? The verse from which the requirement to visit one's Rebbi is derived mentions only Rosh Chodesh and Shabbos. It makes no mention of Yom Tov, and thus it does not provide a source for the obligation to visit one's Rebbi on Yom Tov.
(a) The RITVA (here, and in Rosh Hashanah 16b) addresses this question. He says that the Mitzvah to visit one's Rebbi includes three parts. First, when one's Rebbi is in the same town, he is required to visit his Rebbi every day. Second, when one's Rebbi is outside of the town but within the Techum Shabbos (2000 Amos), he is required to visit his Rebbi only on Shabbos and Rosh Chodesh. Third, when one's Rebbi lives beyond the Techum Shabbos of one's town, he is required to visit his Rebbi only on the festival (he travels before Yom Tov or during Chol ha'Mo'ed when there is no prohibition of Techum).
In the case of the Shunamite woman, Elisha lived outside of the town but within the Techum Shabbos, and thus her husband mentioned only Rosh Chodesh and Shabbos. When Rebbi Yitzchak teaches this Halachah, he does not mention the requirement to visit one's Rebbi every day when the Rebbi lives in the same town, because everyone is heedful of that requirement (since it requires minimal effort). He mentions the Halachah only with regard to Rosh Chodesh and Shabbos, because when the Rebbi lives in a different town, a person tends to neglect the requirement to visit him.
(b) The MAHARSHA explains that if one is required to visit his Rebbi on Rosh Chodesh, then certainly one is required to visit his Rebbi on Yom Tov, even though the verse does not specifically mention Yom Tov. (The Maharsha does not address why Yom Tov is not mentioned in the verse.)
(c) The TUREI EVEN in Rosh Hashanah (16b) and the VILNA GA'ON (Seder Olam Rabah, chapter 3; see also RAV REUVEN MARGOLIYOS in "Olelos," #13) point out that it is odd that the verse mentions Rosh Chodesh before Shabbos. It should mention Shabbos first, because Shabbos comes more frequently than Rosh Chodesh. It must be that the word "Shabbos" in the verse refers to Yom Tov (as the Torah itself refers to Yom Tov as "Shabbos," as in Vayikra 23:16).
(d) Although ideally one should visit his Rebbi every day (in order to learn Torah from him), it is not always possible to do so, because a person is occupied with his work throughout the week. Therefore, the Mitzvah to visit one's Rebbi requires that he visit him only when he is not working. This is evident from the verse in Melachim. The husband of the Shunamite woman mentioned specifically Shabbos and Rosh Chodesh, days on which a woman does not perform Melachah (Shabbos, because of the prohibition of Melachah, and Rosh Chodesh, because of the custom for women to refrain from Melachah on that day), because only on those days would she be obligated to visit Elisha. This implies that on days on which a man does not perform Melachah (Shabbos and Yom Tov), he should visit his Rebbi. A woman, however, is not free to visit the Rebbi during Yom Tov, because on Yom Tov she is occupied with cooking and other responsibilities. A woman has time to visit the Rebbi only on Shabbos and Rosh Chodesh. (ETZ YOSEF, in the name of the IYEI HA'YAM)
(e) The CHANUKAS HA'TORAH (Rosh Hashanah 16b) explains that since it is inappropriate for a woman to visit the Rebbi when his Talmidim are there (see Kidushin 81a), the only time she would be obligated to visit him is when the Talmidim are not there. Thus, the husband of the Shunamite woman asked her why she was going to the prophet when it was not Rosh Chodesh or Shabbos -- days on which the Talmidim are not with their Rebbi, but are home. The verse implies that she has no obligation to visit the Rebbi on the festival, which must be due to the fact that on the festival, his Talmidim visit him. Hence, the verse indeed teaches that one is obligated to visit his Rebbi on the festival!
(f) RAV YONASAN EIBESHITZ (Ya'aros Devash 1:12 and elsewhere) explains that during the times of the Beis ha'Mikdash (when Elisha lived), everyone would go to greet the presence of the Shechinah in Yerushalayim. They would visit the Rebbi only on Shabbos and Rosh Chodesh, when there was no requirement to go to Yerushalayim. After the Churban, the practice was instituted to visit the Rebbi in place of going to Yerushalayim, because a Talmid Chacham reflects the presence of the Shechinah. (See also ARUCH LA'NER, and MALBIM to Melachim II 4:23, who give similar explanations.)
(g) The NODA B'YEHUDAH (OC 2:94) suggests the opposite approach. When the verse mentions Rosh Chodesh and Shabbos, it includes Yom Tov as well. It refers to all days that have additional Kedushah, days on which an additional Korban (the Korban Musaf) is offered. Due to the holiness of those days, the Rebbi has a heightened ability to influence his Talmidim, and his Talmidim are more receptive to his influence. Hence, a Talmid should visit his Rebbi on those days. However, a Talmid is not obligated to visit his Rebbi on all of those days, lest he give more honor to his Rebbi than he gives to the Shechinah (which he visits only on the three festivals). The Gemara in Kidushin (33b) teaches that it is not proper for the honor of the Shechinah to be less than the honor of one's Rebbi, and thus the obligation to visit one's Rebbi can apply only as much as, but not more than, one is obligated to visit the Shechinah. Therefore, the Gemara says that one is obligated to visit his Rebbi on each of the three festivals.
Based on this, the Noda b'Yehudah explains that today, when the Beis ha'Mikdash has not yet been rebuilt, there is no obligation to visit one's Rebbi during the festival (unless, of course, one goes with intent to learn Torah from him), since there is no obligation to visit the Shechinah at the Beis ha'Mikdash. The honor given to one's Rebbi should not be greater than the honor given to the Shechinah.
Accordingly, The TUR and the SHULCHAN ARUCH -- who record only the Halachos that are relevant in practice in when the Beis ha'Mikdash is not standing -- omit this Halachah. The RAMBAM, though, mentions this Halachah (Hilchos Talmud Torah 5:7), because he includes all of the Halachos that are relevant when the Beis ha'Mikdash is standing.
(See also MAHARATZ CHAYOS to Rosh Hashanah 16b, CHIDUSHEI GE'ONIM in the Ein Yakov, and EINEI SHMUEL for other approaches. See also DIVREI SHALOM 2:25.)
2) REBBI ELIEZER'S PRACTICE NEVER TO SAY ANYTHING HE DID NOT HEAR FROM HIS TEACHERS
QUESTION: Rebbi Yochanan b'Rebbi Ila'i asked Rebbi Eliezer whether one may cover a Sukah with a sheet on a sunny day, when the heat causes the occupants discomfort. Rebbi Eliezer did not answer the question, because it was his practice never to say a Halachah which he did not hear from his Rebbi. The Gemara in Yoma (66b) relates a similar interaction wherein Rebbi Eliezer did not answer a number of questions because he did not hear the answers from his Rebbi.
The Acharonim ask that on several occasions Rebbi Eliezer seems to contradict this practice. In the debate of "Tanur Shel Achnai" (Bava Metzia 59b), Rebbi Eliezer declared a certain type of oven to be Tahor when all of the other Chachamim ruled that it was Tamei. The Chachamim acted harshly with him and excommunicated him. The RAMBAN there explains that they were strict with him because he acted in the manner of a "Zaken Mamrei." A "Zaken Mamrei" is a sage who opposes the opinion of the rest of the Chachamim, when their opinion is based on a tradition and the opposing sage's opinion is based on his own logic. In the times of the Beis ha'Mikdash, a "Zaken Mamrei" was punished with death (Sanhedrin 88a). Since Rebbi Eliezer's opinion in that case was based on his own logic and opposed the opinion of the Chachamim which they had received from their teachers, his conduct was similar to that of a "Zaken Mamrei," and thus the Chachamim excommunicated him.
In that case, Rebbi Eliezer presented an opinion that he did not hear from his Rebbi. How is his conduct in that case to be reconciled with his practice never to say anything that he did not hear from his Rebbi? (CHAVOS YA'IR #94, DH uv'Emes)
In addition, Avos d'Rebbi Nasan (chapter 6) relates that Rebbi Eliezer was once asked by his Rebbi to rise and speak. He declined, but his Rebbi and the other Talmidim prevailed upon him and he consented. He discoursed in ways that "no ear had ever heard before" -- including his Rebbi's! (RAV CHAIM SHMUELEVITZ zt'l, Sichos Musar 5731, #23)
(a) The SEFAS EMES in Yoma (66b) answers that the practice not to say anything that one did not hear from his Rebbi is a form of showing honor for one's Rebbi. This form of honor applies only when the Rebbi is alive. Rebbi Eliezer said things that he had not heard from his teachers only after they had died.
This explains why he said an original teaching in the case of "Tanur Shel Achnai." However, in the incident related in Avos d'Rebbi Nasan, his Rebbi clearly was alive, as it was his Rebbi who asked him to speak. Perhaps in that situation, Rebbi Eliezer showed honor to his Rebbi by heeding his request to relate a novel teaching that he had not heard from his Rebbi.
(b) The CHAVOS YA'IR answers that Rebbi Eliezer certainly discussed Halachos with his teachers and colleagues and offered his own novel teachings. However, when he was called upon to issue practical Halachic rulings, he would say the Halachah only as his Rebbi had taught it to him (or when his Rebbi had agreed to his opinion). In the case of "Tanur Shel Achnai," he did not issue a Halachic ruling. Rather, he argued with the opinion of the Chachamim because he disagreed with their logic.
This approach, however, is difficult to understand, because in the incident of "Tanur Shel Achnai," the Gemara says that the Chachamim brought all of the ovens that Rebbi Eliezer had ruled to be Tahor and destroyed them, in protest to his opinion. This clearly shows that he had issued practical Halachic rulings concerning many ovens.
The Chavos Ya'ir apparently understands that the Chachamim brought all of the ovens that Rebbi Eliezer had wanted to declare Tahor, but he never actually declared them Tahor.
(c) RAV CHAIM SHMUELEVITZ zt'l explains that Rebbi Eliezer certainly said Halachos that he did not hear from his teachers. However, he said them only when he had determined that his teachers would have come to the same conclusion.
The incident recorded in Avos d'Rebbi Nasan supports this answer. The Tana there relates that after Rebbi Eliezer finished his discourse, his Rebbi approached him and kissed him on the forehead. This implies that his Rebbi was happy that Rebbi Eliezer had mastered his teachings and was able to come to the same conclusions that he would have taught himself.