On the previous daf we learned about a case where the dividing wall between two courtyards collapses on Shabbat, and how Rava and Abayye agree that we should apply the rule that has been taught before (Eiruvin 17a) that once an area was declared permitted with regard to the rules of eiruvin it remains so until after Shabbat.
On our daf we are introduced to a disagreement about this rule. Rav rejects the rule and says that the residents are no longer allowed to carry beyond the most basic four cubits around them. Shmuel argues that they can carry to where the wall originally stood.
The Gemara relates that this disagreement was derived from an actual event, when Rav was visiting Shmuel and they found themselves in a courtyard where the wall had fallen. Shmuel ordered a cloak be hung between the courtyards and that people could continue carrying as before. Rav did not comment, but he turned away, indicating that he disagreed with Shmuel’s ruling.
The Gemara concludes that Shmuel did not really believe that even the cloak was necessary to allow the residents to continue carrying, and that he hung it simply to offer some privacy to each side. In way of explaining Rav’s behavior, the Gemara argues that since it was Shmuel’s hometown, Rav did not want to publicly disagree with Shmuel’s ruling, but he did want people to understand that his opinion differed from the one that was being put into effect.
Tosafot point out that Rav was uncomfortable with Shmuel’s ruling on two different planes. Aside from objecting to the people in each courtyard carrying, since he believed that reestablishing the wall by means of a cloak was a significant act, it should have been forbidden on Shabbat because of binyan – building. Shmuel did not feel that there was a real need for this division, so he had no reason to keep from putting up the cloak in order to offer a modicum of privacy to the residents.
The Meiri raises the question of how Rav could have avoided a public argument with Shmuel. Even if it was Shmuel’s hometown, we rule that in situations where a transgression will take place, concern for wrongdoing is greater than issues of personal honor. He answers that this particular situation was a relatively minor Rabbinic issue, and in such cases concern for another sage’s honor is more important than the potential transgression. The Ritva explains that in this case we are dealing with a question that had not yet been decided, so it would have been inappropriate for Rav to argue the ruling with Shmuel in Shmuel’s hometown.
In fact, the halakha follows Shmuel’s ruling.