Yerushalmi Eruvin 1:2 ירושלמי עירובין א׳:ב׳

MISHNAH: The legitimization of an alley: the House of Shammai say by lath and beam⁴A beam must have a minimal width as indicated in Mishnah 3, there is no requirement of minimal thickness or strength for the lath, which is only needed to indicate the place up to where the dwellers in the alley may carry on the Sabbath.; but the House of Hillel say, either by lath or by beam; Rebbi Eliezer says, two laths⁵On both sides of the alley.. A student⁶According to the Babli, this was R. Meїr, the only Sage of whom it is known that he studied first under R. Ismael and then under R. Aqiba. said before Rebbi Aqiba in the name of Rebbi Ismael that the Houses of Shammai and Hillel did not disagree about an alley which is less that four [cubits wide] that it is [permitted] either by lath or by beam; about what did they disagree? About one wider than four [cubits] up to ten⁷Since for alleys wider than 10 cubits both Houses agree that one needs “a shape of a door,” i. e., two laths and a beam over them. where the House of Shammai say by lath and beam; but the House of Hillel say, either by lath or by beam. Rebbi Aqiba said, they disagree in both cases.

HALAKHAH: “The legitimization of an alley,” etc. What laths¹⁶⁷This refers to R. Eliezer who in Mishnah 2 requires two laths to permit an alley. The first question is whether he also requires a beam following the House of Shammai or no beam following the House of Hillel. Even though in the Babli R. Eliezer is called a Shammaite, it seems that in general he was extremely conservative and objected to all innovations. Therefore his opinion might show what practice was before schools developed in Pharisaic Judaism. The second question refers to Mishnah 6, where R. Yose sets minimal standards for the width of laths but is opposed by the majority.? Two laths and beam following the House of Shammai? Laths but no beam following the House of Hillel? Three [hand-breadths wide] following Rebbi Yose? Arbitrarily small following the rabbis? Let us hear from the following¹⁶⁸Tosephta 1:2, Babli 1 11b/12a. In the Babli and one Tosephta ms. the name is ben Perida; the other sources have פריה, פירה, פריד.: “It happened that Rebbi Eliezer went to his student Rebbi Yose ben Perora at Oblin. He showed him an alley where there was only one lath. He told him, make it two laths. He said to him, what? Are you telling me to close it off? He told him, let it be closed; there is an argument for the domains of the Sabbath in this respect¹⁶⁹The objection was that since the alley, while not a thoroughfare, is public property, it is not possible to close it off as private property. R. Eliezer’s answer is that property rights are no argument for the rules of the Sabbath which are only based on use.?” This implies three following Rebbi Yose. If you would say, arbitrarily small following the rabbis, does arbitrarily small close off¹⁷⁰Since R. Eliezer agrees that two laths put at right angles to the roadway would in effect close it off it is clear that these cannot be of negligible width.?

It was stated, practice follows the student, for if it were not so, would we say following the House of Shammai¹⁷¹Since the student in Mishnah 2 affirms the tradition of the House of Hillel and only gives a new interpretation of the position of the House of Shammai, there should be no question of practice which is not supposed to follow the House of Shammai.? Could practice follow the House of Shammai rather than the House of Hillel? But since it was stated¹⁷²Babli 12a (middle). In Tosephta 1:3 (and the first version in the Babli) the reading is “four cubits”. The reference is to the width of the alley., “Rabban Simeon ben Gamliel says, an alley which is not four hand-breadths deep does not need a beam.” The words of the Sages? Rav Ḥuna in the name of Rav: An alley which is less than four cubits does not need anything¹⁷³In general the majority of the Sages has to be followed against Rabban Simeon ben Gamliel (in the theory of the Babli, except for Rabban Simeon ben Gamliel quoted in the Mishnah); but in this case it was stated that practice follows the student who required either lath or beam for any alley irrespective of width..