That’s a good question TB Eruvin 20

According to the Torah “Three times a year- on Passover, on Shavuot, and on Sukkot-all your males shall appear before the Lord your God in the place that He will choose. They shall not appear before the Lord empty-handed, but each with his own gift, according to the blessing that the Lord your God has bestowed upon you.” (Deuteronomy 16: 16-17) Of course, the place where all Israelites congregated on the pilgrimage holidays was Jerusalem because the holy Temple stood there. When there are no pandemic restrictions, many Diaspora Jews still go to celebrate these pilgrimage holidays in Jerusalem. Today making our way to Jerusalem is quite easy. We hop on a plane and hours later we are in Israel and a sharut ride away from our final destination.

 Even within the Land of Israel, a pilgrim’s journey to the Holy City was not easy back in biblical and talmudic days. The Israelite had to transport his gift whether it was a grain offering or an animal sacrifice. The journey had to take days and the animals he brought had to be taken care of. Obviously, the Israelite camped out each night around a water source, most likely a well. Now the well was in the public domain, (רשות הרבים), but the well itself constituted a private domain, (רשות היחיד ) because it met the minimum dimensions of a private domain. The minimum dimensions of a private domain is 4 by 4 handbreadths (טפחים) surrounded by a wall that is at least 10 handbreadths tall. There lies in the problem. Since on Shabbat a Jew is not allowed to transfer anything from the private domain into the public domain (and vice a versa), how could the Israelite draw water his animals because he would be transferring the water drawn from a private domain to a public domain?

 We learned in the first chapter of Eruvin how to adjust an alleyway consisting of three walls opening up to the public domain. To demand the pilgrim to build three walls around each well each night would be a terrible burden and probably an impossibility. Consequently, the rabbis permitted for these pilgrims a great leniency. The first Mishnah of the second chapter describes what the person must do to create virtual walls to allow him to draw water on Shabbat.

 “MISHNA: One may arrange upright boards [passin] around a well in the public domain in order to permit drawing water from the well on Shabbat. A well is usually at least four handbreadths wide and ten handbreadths deep. Therefore, it is considered a private domain, and it is prohibited to draw water from it on Shabbat, as that would constitute a violation of the prohibition to carry from a private domain into a public one. The Sages therefore instituted that a virtual partition may be built in the area surrounding the well, so that the enclosed area could be considered a private domain, thus permitting use of the well and carrying of the water within the partitioned area.

 In this specific instance, the Sages demonstrated special leniency and did not require a proper partition to enclose the entire area. For this purpose, it suffices if there are four double posts [deyomadin] that look like eight single posts, i.e., four corner pieces, each comprised of two posts joined together at right angles; this is the statement of Rabbi Yehuda. Rabbi Meir says: There must be eight posts that look like twelve. How so? There must be four double posts, one in each corner, with four plain posts, one between each pair of double posts.

The height of the double posts must be at least ten handbreadths, their width must be six handbreadths, and their thickness may be even a minimal amount. And between them, i.e., between the posts, there may be a gap the size of two teams [revakot] of three oxen each; this is the statement of Rabbi Meir.

 Rabbi Yehuda disagrees and says: There may be a slightly larger gap, the size of two teams of four oxen each, and this gap is measured with the cows being tied together and not untied, and with the minimal space necessary for one team to be entering while the other one is leaving. It is permitted to bring the posts closer to the well, provided that the enclosed area is large enough for a cow to stand with its head and the majority of its body inside the partitioned space while it drinks.

 It is permitted to distance the boards from the well and expand the enclosed area by any amount, i.e., as much as one wishes, provided that he increases the number of upright boards between the double posts. Rabbi Yehuda says: The partitioned area may be expanded up to an area of two beit se’a, which is an area of five thousand square cubits.

The Rabbis said to him: They only spoke of an area of two beit se’a with regard to a garden or an enclosure used for storing wood, scrap, and the like [karpef]. But if it was a pen [dir], or a stable [sahar], or a backyard, or a courtyard in front of the house, even if it had an area of five beit kor or even ten beit kor, it is permitted. And it is permitted to distance the boards and expand the enclosed area by any amount, provided that one increases the upright boards between the double posts.” (Eruvin 17b-18a, Sefaria.org translation)

That’s a long introduction to daf TB Eruvin 20 because the previous dappim contained a lot of midrashim, of which I wrote about instead of the Mishnah itself. Since TB Eruvin 19b the Gemara returned to discussing the laws of these upright boards making a virtual wall around the well (פַּסִּין לְבֵירָאוֹת). Abaye asks six different questions “what if?” What if the well runs dry on Shabbat, are these virtual walls still valid? What if it rains on Shabbat and the well becomes functional but again, do these virtual walls become valid? What if a courtyard’s walls extend into the area of the virtual wall, may one transfer something from the courtyard into the area surrounding the well?

The Gemara answers these questions and others in its own fashion. Since the need for such virtual walls around a well today is only hypothetical, you can go to the page itself to see the answers. What interests me is the Gemara’s willingness to entertain all those questions. What parent or teacher hasn’t been beleaguered by a child asking a lot of, “but what if” questions one right after the other! We can learn a lesson from this daf. Be patient when people are asking you a lot of sincere questions. Each question deserves an answer. I always want my students to ask questions whether they are children or adults. Consequently, I validate the question by saying, “That’s a good question and that there’s no such thing as a stupid question, only stupid answers.” Only by asking questions can a person really learn.