Introducing Rav Yosef TB Eiruvin 10

Everybody agrees that when the side post (lekhi- לחי) is placed on the interior wall of the alleyway and it can be seen by those in the alleyway, but not by the people in the public domain (נִרְאֶה מִבִּפְנִם וְשָׁוֶה מִבָּחוּץ), this side post is a kosher side post that permits carrying in the alleyway. Starting on yesterday’s daf and continuing on today’s daf TB Eiruvin 10, the Gemara discusses the case whether the side post which is seen by the people in the public domain, but not in the alleyway (נִרְאֶהִ מִבָּחוּץ וְשָׁוֶה מִבִּפְנִם) permits carrying in the alleyway. The best way to visualize this is to see the side post extending out into the public domain. The people in the public domain can clearly see the lekhi, but it appears to be just an extension of the wall to those inside the alleyway.

The Gemara spends a long time discussing this issue. At one juncture in the discussion, the Gemara arrives at this conclusion. “Rather, can we not conclude from the baraita that a side post that is visible from the outside but appears to be even with the wall from the inside is not considered to have the legal status of a side post? The Gemara concludes: Indeed, conclude from this. Rav Yosef said: I did not hear this halakha” (Sefaria.org translation)

Let me introduce to you Rav Yosef and explain the significance of his statement. “Rav Joseph was a disciple both of Rav Huna and Rav Judah, especially of the latter. Rav Joseph soon became famous as a great Talmudic scholar, and Rav Nachman, the dean of the yeshiva in Nehardea, Rav Huna's friend, acclaimed Rav Joseph as "Sinai"-meaning to say that he had a perfect knowledge of the complete Torah. Rav Nachman, who was not much older than Rav Joseph, was the son-in-law of the "Exilarch" ("Head of the Exile"), and was also dean of the yeshiva in Nehardea, as we have mentioned. Rav Joseph learned Torah also from him, for some time.

“Approximately in the year 4060 (300) the leaders of the yeshivoth in Pumbeditha and Sura died. They were succeeded by Rabbah bar Nachmani in Pumbeditha, and Rav Chisda in Sura. Rabbah was Rav Joseph's colleague, and we find many laws and sayings in the Talmud that were said in the name of both of them: "Rabbah and Rav Joseph both said..." Actually, after Rav Judah's death, the Sages did not know whom to appoint as head of the yeshiva in Pumbeditha, because Rabbah and Rav Joseph were both very great Talmudic scholars. The Sages, therefore, sent messengers to Eretz Yisroel to inquire as to which is more important, a "Sinai" or "an uprooter of mountains," meaning, in other words, someone with a vast knowledge (Sinai) or someone with a sharp brain (an uprooter). (Rabbah was famous for his sharp brain). The Sages of Eretz Yisroel replied that a "sinai" was more important, but even so, Rav Joseph declined the honor of becoming dean, and therefore his colleague was chosen instead. (When Rabbah died at the age of 40, Rav Yosef took his place as the head of the yeshiva in Pumbedoitha-gg)

“(Now to the relevant part of his biography relating to our sugiyah-gg) In his old age, Rav Joseph became blind, due to a severe illness, which also affected his memory. He still continued his teachings, however, and his beloved pupil, Abaye, used to remind him many times of a law or a saying that Rav Joseph himself had previously said but had forgotten.” https://www.chabad.org/library/article_cdo/aid/112297/jewish/Rav-Joseph.htm

 Back to our Gemara. Indeed Abaye reminded his teacher what he once taught on this subject. “His student Abaye said to him: You yourself told us this halakha, and it was with regard to this that you told it to us. As Rami bar Abba said that Rav Huna said: With regard to a side post that extends along the wall of an alleyway and beyond, in which case it appears from the inside to be a continuation of the wall but due to its narrow width it is clearly visible as a side post from the outside, if that side post is less than four cubits long it is considered to have the legal status of a side post. And one may use the alleyway up to the inner edge of the side post. However, if the side post itself extends four cubits, the alleyway has no side post and it is considered to have the legal status of an alleyway, and it is prohibited to utilize the entire alleyway. And you said to us about this: Learn from this statement three halakhot with regard to eiruvin. Learn from it that in the area between the side posts it is prohibited to carry, as Rav Huna rules that one may use the alleyway only up to the inner edge of the side post. And learn from it that the minimal length of an alleyway is four cubits. And learn from it that a side post that is visible from the outside but appears to be even with the wall of the alleyway from the inside is considered to have the legal status of a side post.” (Sefaria.org translation)

“Rav Joseph's disciples respected him just as before when he was not blind and had a clear knowledge of the Torah. Rava, his pupil, used to walk backwards when leaving Rav Joseph's presence, as one does when leaving a great Talmudic scholar or a king, even though Rav Joseph was blind and did not see him. Rava used to walk backwards until he reached the doorstep of the house. When Rav Joseph was told of Rava action, Rav Joseph blessed him that he should become a great man and he also should receive great honor. Rava actually did become the greatest Torah authority after his colleague Abaye died.” https://www.chabad.org/library/article_cdo/aid/112297/jewish/Rav-Joseph.htm

As I’ve grown older and my memory has failed me from time to time, I can imagine how Rav Yosef who was considered in his prime “Sinai” felt when he couldn’t remember what he taught and had to be reminded by his students. I hope that the tremendous love and respect he received from his students assuaged his embarrassment for his memory lapses.

His students should serve as our role model how we should treat our elderly whose mental capacities have diminished because of old age, dementia, or Alzheimer’s.  Even though they are not the same now as they were in their prime, they still deserve our great respect.