If the eruv in question is known to be kosher, and under reliable supervision, then there is no problem making use of it. There are some who wish to follow the opinion of the Rambam, who holds that the distance of the enclosure covered by the actual mechitzos (halachic ‘barriers’) should be greater than that covered by tzuros ha’pesach (halachic ‘doorways’). This principle is called “omed merubah al haparutz,” that is, the real barriers must be greater than the open areas in which doorways are used to complete the enclosure. Most eruvin do not adhere to this restriction, and those who wish to be machmir should consult with the Rav in charge of the particular eruv they wish to use.
The rebuttal: It is ironic that the main subject of this chapter, large city eruvin, which Rav Belsky is seeking to malign are usually classified as Rambam eruvin. In large cities, the houses are situated closely enough together that they can be classified as mechitzos through omed merubeh al haparutz and would, therefore, satisfy shitas haRambam (A Rambam Eruv in Brooklyn?). Consequentially, according to the Rambam, this creates an interesting dichotomy as there are fewer grounds to be stringent in large cities then in smaller ones where the houses are too spread out to be halachically joined as mechitzos. However, I must emphasize that besides for a few yachidim, the minhag Europe was not to be stringent regarding shitas haRambam at all.
Shulchan Halevi: Bungalow colonies: In a bungalow colony, as long as the eruv was installed correctly (al pi din), there is almost never a question as to its kashrus. This is because these small collections of summer cabins are usually not considered to be a proper public domain (reshus ha’rabbim), even considering the country road that might bisect it. Even in the view of the Mishkenos Yaakov, such an area is not a public domain, and the eruv is kosher. Some bungalow colonies may nevertheless have public domains running through the area enclosed by the eruv, so it is always advisable to consult with the Rav in that colony for specific information regarding each eruv.
The rebuttal: Actually the Mishkenos Yaakov maintains that any town road (unroofed) which is 16 amos wide is classified as a reshus harabbim. Accordingly, if the public road that bisects a colony is 16 amos wide, it would pose a problem. However, as Rav Belsky mentions further on, our custom was not to follow the Mishkenos Yaakov but the Bais Ephraim, so I do not comprehend why he even mentioned this opinion. Paradoxically, there is a possibility that the Brooklyn eruvin which Rav Belsky is inveighing against would satisfy the Mishkenos Yaakov since the mechitzos encompassing Brooklyn at the waterfront do not have a rabbim traversing them as opposed to these colony eruvin (see Mishkenos Yaakov, O.C. 122, p. 144).
Shulchan Halevi: City eruv: Determining the halachah regarding a city eruv is far more complex. It is clearly established in halachah, that a series of tzuros ha’pesach, or open doorways, in a public domain (reshus ha’rabbim) cannot be used for an eruv. What remains as a matter of dispute is precisely what the Torah considers to be a public domain.
The rebuttal: What Rav Belsky fails to mention is that there is a, “clearly established halachah,” that many if not most poskim uphold that me’d’Oraysa a tzuras hapesach would reclassify a reshus harabbim as a reshus hayachid. Accordingly, the requirement of delasos is only me’d’rabbanan (Rosh Yosef, Shabbos 6b; Shulchan Aruch HaRav, O.C. 364:4; Tzemach Tzedek, Eruvin the end of Perek 5; Aishel Avraham, siman 345; Gaon Yaakov, Eruvin 11a; Yeshuos Malko, O.C. 21; Aruch HaShulchan, O.C. 364:1, and Kaf HaChaim, O.C. 364:12). Since the requirement of delasos is me’d’rabbanan, we can be lenient [safek d’rabbanan l’kulla] and apply any additional heter to remove the requirement of delasos (Kanah V’Kanamon, 5:56; Livush Mordechai, 4:4, and Bais Av, 2:9:3). It is incredible that Rav Belsky would state with such surety that a tzuras hapesach would not suffice in a public domain, and that he would disregard some of the greatest poskim who uphold otherwise.
Shulchan Halevi: The early Rishonim disagree on whether a domain must contain six-hundred thousand people to be considered ‘public.’ Rashi and Tosafos hold that it must, while most of the Rishonim disagree, and maintain that even if there are not six-hundred thousand people in a particular area, it may still be a full-fledged public domain.
The rebuttal: It seems that Rav Belsky is repeating the Mishnah Berurah’s [Mishkenos Yaakov’s] argument but is neglecting to mention that they have been clearly superseded. At this point in time, it is no more a matter of debate; we now know that the overwhelming majority of Rishonim maintain that shishim ribo is a fundament of a reshus harabbim (The Overwhelming Majority of Rishonim Maintain that Shishim Ribo is a Criterion of a Reshus Harabbim). Anyone who has learned through this inyan should be familiar with this reality, and the fact that Rav Belsky still argues otherwise shows him up to be prejudiced when the matter is city eruvin.
Shulchan Halevi: About one hundred and seventy-five years ago, two major responsa were written regarding eruvin. The Mishkenos Yaakov wrote against the practice of building eruvin in large cities, even if their population did not reach six-hundred thousand, while the Beis Ephraim justified the construction of such eruvin, as long as the population did not exceed six-hundred thousand people, based on Rashi and Tosafos. The custom in Europe in most communities was to rely on the Beis Ephraim, Rashi and Tosafos, that a Torah-sanctified reshus ha’rabbim must be populated by six-hundred thousand people. Since most European towns did not meet that criterion, eruvin were permitted during that period.
The rebuttal: This is simply incorrect. No one argues that the Bais Ephraim maintains that shishim ribo is conditional of a city. Anyone who argues as such did not learn through the Bais Ephraim. The only disagreement regarding the Bais Ephraim is how he applied the criterion of shishim ribo to a street. Some want to argue that the Bais Ephraim would classify a road as a reshus harabbim just if it was possible for shishim ribo to traverse the street (actually, nobody of stature maintains as such). However, the poskim understand that the Bais Ephraim would only classify a street as a reshus harabbim if, at times, 600,000 people actually traverse the road itself (The Overwhelming Majority of Achronim Maintain That the Shishim Ribo Has to Traverse the Street Itself). Even the Mishkenos Yaakov admits that the criterion of shishim ribo is conditional of the street (siman 121). The fact that there were cities in Europe (see below) containing shishim ribo that maintained eruvin is proof that they relied on the fact that no street contained shishim ribo and not just the city itself.
Shulchan Halevi: With the passing of time cities became larger until it became common for Jews to live in cities, with populations in the hundreds of thousands and even millions. This means that even Rashi and Tosafos would consider these cities full-fledged ‘public domains,’ and the main heter of the Beis Ephraim no longer applies.
The rebuttal: Since Rav Belsky is on the subject of the European custom in regards to eruvin, how could he not recognize that the custom was to established eruvin even in cities with populations greater than shishim ribo? Warsaw, Lodz and Odessa all maintained eruvin despite the fact that their populations were greater than shishim ribo. Moreover, the Divrei Malkiel (4:3) clearly states the custom in Europe was to rely on the fact that no street had shishim ribo traversing therein. Even Rav Moshe Feinstein zt”l agreed that in Europe the minhag was to establish eruvin in cities containing shishim ribo (consequentially he required a population of three million; The Requirement of Shishim Ribo: Is It Conditional on a City?). I challenge Rav Belsky to list one posek other than himself and Rav Moshe Bick zt”l who upholds that shishim ribo is conditional of the city (regarding the Achiezer see Part 1: The Achiezer Explained, Part 2: The Achiezer Explained). Moreover, the Bais Ephraim mentions other grounds to allow large city eruvin that Rav Belsky conveniently omits (the fundament of mefulash and that we pasken lo asu rabbim u’mevatlei mechitzta). Consequentially, even without relying on the criterion of shishim ribo, the Bais Ephraim would allow our eruvin since there are additional conditions of a reshus harabbim that were not met.
Shulchan Halevi: In the interest of maintaining the viability of eruvin in large cities, some modern-day Rabbanim began to search for various rationales to avoid classifying large cities as bona-fide public domains.
The rebuttal: I think that Rav Belsky should have known whom he is classifying as modern-day rabbanim who allowed eruvin even in large cities. These include the Divrei Malkiel, Rav Chaim Berlin (Oddesa eruv), the Achiezer (Paris eruv), Rav Shlomo Dovid Kahane (Warsaw eruv) and the Chazon ish (all large cities). I think the contemporary rabbanim are in very good company. Is Rav Belsky suggesting that these Gedolei Haposkim acted like modern-day rabbanim who seek leniencies that are unsubstantiated? Is Rav Belsky suggesting that the renowned Chazon Ish’s heter that sanctions large city eruvin exposes the Chazon Ish as a modern-day rabbi?
Shulchan Halevi: Sidewalks: One suggestion that has been made is that sidewalks are not public domains, but simply “edges of the public domain” (tzidei reshus ha’rabbim). If this were indeed the case, it would be permissible to set up an eruv on the sidewalk. Presumably, the rational is that cars and other vehicles do not generally drive on the sidewalk; they drive on the paved road, which contains no obstacles and upon which it is easier to travel. On the other hand, the Gemara defines tzidei reshus ha’rabbim as a market place where peddlers sell their wares and pedestrians cannot pass through with ease. With this in mind, it becomes very difficult to classify our sidewalks, which were made for the express purpose of permitting the free flow of pedestrian traffic (hiluch ha’rabbim), as tzidei reshus ha’rabbim, where pedestrian terrific is limited.
The rebuttal: To the best of my knowledge, the first and only posek to suggest this heter was Rav Belsky himself. In 1999 when the Boro Park eruv was established, Rav Belsky gave a shiur in Yeshivah Torah Vodaath vehemently objecting to the eruv. In his zeal to excuse away the fact that a Boro Park Chassidshe shul had erected an eruv enclosing their sidewalk, Rav Belsky suggested that they were relying on a tenuous heter of tzidei reshus harabbim. The only similar heter suggested (and possibly this is what it is being conflated with) is that since the streets are designated for cars ― and there is a requirement that the whole 16 amos must be suitable for people ― the streets and the sidewalks on either side of the street are not considered connected to form one contiguous 16 amos (Tikvas Zechariah, p. 40 and Divrei Yatziv, 2:172:13; see also Oim Ani Chomah, siman 63). Additionally, the parked cars themselves serve as mechitzos as they separate the sidewalk from the street. Consequentially, the streets are not considered 16 amos wide (Nesivos Shabbos, 3:1:2). However, these heterim are really only being used as a snif l’heter in conjunction with other heterim to allow eruvin in large cities.
Shulchan Halevi: Individual streets: Another mistaken idea is that individual streets which cannot accommodate six-hundred thousand people at a time are not considered reshus ha’rabbim, even if they are part of a city whose population exceeds that number. This innovative distinction fails when subjected to halachic scrutiny. The undisputed halachah is that an ally-way open on both ends (mavui mefulash) to a public domain is also classified as a public domain. Side streets are no better than alley-ways, and open-ended side-streets must also be classified as part of the public domain. Thus, the argument for constructing an eruv on side-streets becomes completely baseless. More fundamentally, the fact that open-ended alley-ways are considered part of the public domain negates the notion that for any particular street to be deemed a public domain, it would need to have six-hundred thousand residents. It is unthinkable that an ally-way could accommodate such a number, yet it certainly forms part of the public domain.
The rebuttal: Rav Belsky is totally mistaken regarding mavoi mefulash. No Rishon or Achron who upholds that shishim ribo is a fundament of a reshus harabbim maintains that an open ended alleyway [mavoi mefulash] does not itself require shishim ribo traversing the mavoi (or according to some poskim, traversing only at times) in order to be classified as a reshus harabbim itself (see for starters Tosfos, Shabbos 64b; moreover, this Tosfos is proof that the criterion of shishim ribo is conditional of the street). Furthermore, even if one were to find an Achron who would agree to Rav Belsky’s argument, it is totally irrelevant whether or not a mavoi mefulash to a reshus harabbim would itself require shishim ribo traversing therein, since at the outset, we do not have a reshus harabbim ― a street including shishim ribo ― that the mavoi is mefulsh to. [The Bais Ephraim (and other poskim) maintains that when a mavoi is mefulash in its length into a street classified as a reshus harabbim, we do not require shishim ribo traversing the mavoi for it to be classified as a reshus harabbim. However, Rav Belsky is referring to side-streets which run perpendicular to a street classified as a reshus harabbim; in which case, even the Bais Ephraim would require shishim ribo traversing the side street, as well. Additionally, as mentioned above, to begin with there is no reshus harabbim that the side-street is mefulash to. Therefore, the Bais Ephraim does not concern us at all.] Consequentially, Rav Belsky’s argument, “the fact that open-ended alley-ways are considered part of the public domain negates the notion that for any particular street to be deemed a public domain, it would need to have six-hundred thousand residents,” is incorrect. Open-ended alleyways are classified as a reshus harabbim only if they contain shishim ribo (and meet the other criterion of reshus harabbim, as well ― there are some halachic distinctions to take into account when classifying an open-ended alleyway and a street as a reshus harabbim such as their required widths and the number of mechitzos).