Q. Since The Community Eruv kuntres is intended for the layman isn’t it usurping the power of the local rabbanim? Shouldn’t hilchos eruvin only be discussed by rabbanim?
A. Why is a kuntres that elucidates the halachos of eruvin any different than any English halachah sefer that is published — aren’t they all intended for the layman? Why are some people so afraid to let the Flatbush community examine the real issues? Why should eruvin be different than any other halachic issue? Despite having shown how the halachah supports an eruv, The Community Eruv kuntres actually encourages the layperson to consult with his rav as stated clearly on page 3 of the kuntres, “At the outset, however, we would like to clarify that this introduction to eruvin should not be used as the final word on the matter as we strongly advocate that you follow the p’sak of your own rav.”
Q. Since the eruv is causing machlokes, wouldn’t it be better not to erect one?
A. Is it the eruv that is causing machlokes, or is it the people fighting the eruv who are causing machlokes? We, who rely on the eruv, are not forcing others to carry. Why are those who oppose the eruv interfering with our right to follow the p’sak of our rabbanim who do allow us to carry? Through the years, rabbanim have always had differing halachic opinions on critical Torah issues, and we have always said eilu veilu divrei elokim chaim. Why should eruvin be any different?
Q. All of the above is very convincing; however, why is it that there is more of a machlokes when an eruv is established than when any other community issue is raised? Is it possible that the reason is that the issue is a d’Oraysa, as some claim?
A. There is no other d’Oraysa that has aroused such a passionate need to be mocheh besides for eruvin. For example, many people maintain that shitas Rabbeinu Tam [72 minutes after shkiah] is an obligatory extension of Shabbos, to the extent that if someone does a melachah at an earlier zeman he is considered a mechalel Shabbos. Shitas Rabbeinu Tam is also a matter of a d’Oraysa, yet people are not mocheh against those who keep an earlier zeman, calling them mechalelei Shabbos. Why is the issue of eruvin any different? Additionally, Hagaon Harav Moshe Feinstein zt”l wrote that when one follows one’s rav on any issue, even on issurei chilul Shabbos, albeit the halachah is not like their rav’s interpretation, no aveirah is transgressed. Therefore, by following our rabbanim, even if others feel that the p’sak is wrong, according to Rav Moshe no transgression has occurred. Why are those who invoke Rav Moshe in their every attempt to discredit eruvin ignoring Rav Moshe’s own rulings? The opposition toward eruvin is irrational and has no support or basis in halachah.
However, eruvin is different than other halachic issues in one significant aspect. Eruvin more than any other issue vests a certain amount of centralized power to the baal ha’machsher. A person publicly carrying in a rav’s eruv is a clear sign of the posek’s influence and support in the community, unlike relying on the rav’s hechsher on food, which is a more private matter. Consequently, there are people who find it incumbent upon themselves not to allow an eruv to be established, and insist that their rav’s opinion is the only one that can be followed. If one were to follow the history of eruvin in cities where there was no central governing rav or Bais Din, one would find that machlokas often erupted as a result of this desire for dominance in community affairs [Krakow 1887, St. Louis 1895, Odessa 1900, New York 1905 to the present, Manchester 1906, Frankfurt am Main 1914, and London 1932 to the present]. Otherwise eruvin would generate the same level of reaction as a mikveh, where every individual just follows the p’sak of his own rav. Which leads to one conclusion, the issue of city eruvin is more of a political one than a halachic one.
 Igros Moshe, O.C. 1:186.