The root of the word eruv is “blend”. This concept describes what occurs whenever one makes an eruv, whether an eruv tavshilin, which allows cooking on Yom Tov for Shabbos (a blending of “cookings”) or an eruv techumos, which allows “increasing” the permitting walking distance on Shabbos (blending two distinct areas) or the eruv chatzeros which allows for carrying between properties on Shabbos (blending of domains). When the Torah chooses to describe our father Abraham’s great commitment to Torah observance, it uses the example of his adherence to eruv to demonstrate that even Shabbos rabbinic decrees were observed by him.1 The eruv is a rabbinic method to allow an otherwise rabbinic restricted activity on Shabbos and Yom Tov.

The common form of eruv is eruv chatzeros. This eruv was established by Shlomo HaMelech to increase shalom between Jews.2 To understand how the eruv operates, it is imperative to explain the prohibition against carrying on Shabbos. As with all of the 39 prohibitions of Shabbos, carrying was practiced in the desert when the Jewish people were constructing the Mishkan. Since we were commanded not to construct the Mishkan on Shabbos, it is understood that any activity involving the construction was therefore forbidden on Shabbos.3

In the Jewish desert encampment, there were three designated domains: public, private and Makom P’tur (no-man’s land, a very small elevated area, i.e. the top of a fire hydrant). The Jews were commanded not to carry from a public to private (or the reverse) and four cubits (about 6-8 feet) in the public domain. (They were allowed to carry from public to Makom P’tur or private to Makom P’tur). The rabbis created an additional domain, a carmelis (from the terms meaning wet and dry – ie. gray area).4 While this domain would be considered non-public on a Biblical level, the rabbis were concerned that it closely resembled a public domain and hence prohibited the activities there associated with a public domain. In addition, the rabbis also prohibited carrying from one private domain to another. The eruv chatzeros would allow this activity provided that certain conditions are met. The reasoning behind this eruv is to connect the non-private and private domains into one large private one. This process is somewhat complex. One can also construct a more limited eruv which will only unify actual private domains, excluding Biblical public and carmelis domains.

If one were to convert a Biblical public domain, one must first establish what constitutes this domain. Here again, several conditions must be met, the roadway must be at least 10 cubits (approx. 15-20 feet) wide, have no obstructions overhead, and it must not be a “dead end”. Some add an additional requirement that it is travelled by 600,000 people on a regular daily basis.5 The issue of those conditions has been grounds for much controversy over the ages because if one is considering an area to be a Biblical public domain, actual gates are required to convert that area to a private domain to allow one to carry on Shabbos.6 Whereas, if the area did not meet all the necessary conditions then it would be considered a carmelis and that area would only require an enclosure of door frames or “tsuris hapesach” to allow for carrying.7 The rationale for door frames is that as a private domain may contain a doorway, it follows that doorways are considered enclosing an area.

The discussion of whether an average city street is a public domain or a carmelis has been the source of many disputes regarding creating eruvim in large cities. Both positions rely on original ideas to determine the correct classifications. The debate is whether to erect the eruv to assist those who would carry inadvertently or are ignorant about the laws of Shabbos vs. the Shabbos observant public who will then carry in an eruv that incorporates leniencies. There is no set precedent, because each situation is unique and is subject to the positions of the rabbinical establishment located there. One should not compare different instances since each has its specific distinctions.

After it is established that a given area is a carmelis, one sets about erecting a series of posts (called lechis) in the areas that are not fenced off. Under certain circumstances, neutral barriers may also be considered contributing to the enclosure. These posts must be at least 10 tefachim (approximately 5 1/3 feet) high, according to the Rambam. These posts may not be placed further than 10 cubits apart, except if the majority of the enclosure is a solid fence.8 Most eruvim rely on the opinion of those who allow greater separation between the posts, as it is very difficult to construct an eruv with a post every 10 amos. Many communities follow the Rambam’s requirement that the entire enclosure must be constructed of doorways less than 10 amos apart and forgo carrying in eruvim that use a separation greater than 10 amos. The shulchan Oruch HaRav rules according to the Rambam’s position.9

It is a common misconception that the actual enclosures constitute the eruv

Taut string or line connects the tops of the posts to complete the enclosure. The lines may not sway in a normal wind. While no physical requirements are made of the post, they must be able to support the lightest of doors. If the line does not pass over the top of the post the eruv is invalid. Ideally the posts should all be the same height since they are supposed to resemble door frames, however, each individual door frame can be a separate height. Although the connecting line should not dip more than 45 degrees, this won’t invalidate the eruv.10

It is a common misconception that the actual enclosures constitute the eruv. In actuality, it is a portion of designated food that is the eruv, but the proper enclosure is always necessary.

After the area is properly enclosed, one is then required to consolidate all the separately owned domains into one. This is accomplished by providing bread in the portion of one grogres (fig-sized amount) for every person involved up to 18 grogres (approximately 2 loaves) and placing it in one of the houses. If there are more than 18 people involved in the eruv, the 18 grogres suffices for all. Now, as all those in the enclosure own bread in one of the properties, they are all one. Matzah is preferred since it keeps longer than bread. After everyone contributes, one person can acquire the bread in the name of all.11 There is a dispute regarding who needs to contribute bread based on whether the grouping is a property owner allowing his property to be used as a common area, or it is a partnership of all area residents. One question in this case is whether the bread collection must be kept with the actual property owner, or if it can be stored in a communal area, such as the shul.12

A blessing is recited while making the bread portion of the eruv and then a text which specifies this eruv allows for carrying between the individual houses and yards. If one is making both an eruv chatzeros and an eruv techumim together, there are opinions that one should amend the brocha to plural, or to spell out the specific eruvim (eruv chatzeros v’eruv techumim).13

While one does not need to consent to be part of the eruv, if one dissents this ruins the eruv. Regarding an eruv in a town, if one has permission of the authorities to construct the eruv it is felt that this overrides requirement of individual consent and a private person may no longer object.14 When there are non-Jewish resident in the enclosure, one is required to procure permission to trespass on his stake of the property by leasing it.15

It should be noted that while this eruv is primarily beneficial for Shabbos carrying, in fact, even on a Yom Tov one must limit his carrying to items required for the holiday.16 An eruv helps make all carrying permitted on Yom Tov. Care should be taken that even with an eruv one does not carry items need for the following day of Yom Tov since that is part of the prohibition of preparing on one holiday for the next. An eruv allows one to carry on Yom Kippur even though in theory one cannot partake of the communal bread.17

Eruv & Kashrus
While at a glance one would not associate an eruv with kashrus, they are in fact, closely related. Admittedly, eruvai techumim would rarely be utilized (unless one needed to spot-check a certain facility on Shabbos which could only be facilitated with an eruv techumim). But eruv tavshilin is utilized in hotel programs when Shabbos follows Yom Tov.18 The event mashgiach must be instructed to correctly make this eruv and remember to implement it.

The eruv chatzeros play a big part in food service events scheduled on Shabbos. The hechsher must determine if an eruv will be required and the mashgiach must be supplied with sufficient time, material and manpower to construct the eruv. This cannot be done while supervising the kitchens. In addition, he should request from management the schedule for deliveries and trash collection since these large trucks may inadvertently destroy the eruv. Instructions must be given that if a kosher eruv is knocked down on Shabbos, it is permitted for a non-Jew to rebuild it on Shabbos.19 As the mashgiach cannot consult with the kashrus agency on Shabbos, it is imperative that he be well versed in these halachos.

Many times an eruv is required because the hotel does not have sufficient storage/refrigeration space, and the caterer must utilize his truck during Shabbos for these purposes. An eruv of 3-4 posts would allow for this activity by connecting the truck to the building. Some caterers supply posts with nails on the tops that are sunk into self-standing cement pails which and can quickly be placed in the proper positions. The posts are connected with fishing line which allows quick construction.

OK mashgichim set aside the loaves of bread for the kosher guests, but it is only required for an event going into Shabbos and can then be eaten. (When an event spans more than one Shabbos, the bread must be saved until the last Shabbos or prepared again before the next Shabbos.)

When the establishment is owned by a Jew, the prevailing opinion is that when a landlord has access to his apartments or keeps his belongings in them (definitely the case in hotels where you are not renting a specific room and the management can change your room at their discretion) then the loaf is not required.20 It is also assumed that a manager has a bed somewhere on the premises. Regardless if a mashgiach sets aside bread for an eruv, he will not make a brocha on it. Of course, during Passover events only Matzah would be used.

There are two possible scenarios when caterers serve guests in a hotel on Shabbos. Either the entire hotel is booked (i.e. Passover), or only a certain number of rooms are books for the Jewish guests (i.e. a bar mitzvah). In the former, since all of the guests are supplied with food from the same kitchen and they have pre-paid, the premises can be “leased” from the non-Jewish ownership for a dollar and no eruv bread is needed since all of the guests are partners in the food. However, the second scenario, where the guests are invited to a simcha, then the host is considered to be a guest as well. Even though the host is supplying the guest with food, it will require a common eruv. However, a brocha is not required over this eruv since some authorities do not require an eruv in this scenario.21

As stated, eruv was established to increase peace among us. The Talmud states that three commandments have a common denominator – height.22 The height of a sukkah, eruv or light of the Chanukah menorah cannot be higher than twenty cubits since the eye will not notice them above that height. The connecting thread between these seemingly unrelated mitzvos is that they all indicate a boundary of sorts. An eruv is a property boundary, the schach of the sukkah marks the boundary of where one may eat during Sukkos, and the Chanukah lights are placed at the boundary of a room (the doorway or window). In the merit of respecting these boundaries and as we celebrate Chanukah, may we merit to be speedily restored to our rightful boundaries in Eretz Yisroel and rebuild the Beis HaMikdash with the coming of Moshiach now.


1 Gemara Yuma, 28b.
2 Talmud Yerushalmi, Eruvin 7, Halacha 9.
3 Gemara Shabbos, 96.
4 Shulchan Oruch, Orach Chaim 346:1-2.
5 Shulchan Oruch, Orach Chaim 345:7.
6 Shulchan Oruch, Orach Chaim 364:2.
7 Gemara Eruvin, 11b.
8 Shulchan Oruch, Orach Chaim 362:9.
9 Shulchan Oruch HaRav, Orach Chaim 362:19.
10 Shulchan Oruch, Orach Chaim 362:11; Sha’ar Tziyon 36.
11 Shulchan Oruch, Orach Chaim 366.
12 Shulchan Oruch, Orach Chaim 366:3.
13 Mishna Brurah, Orach Chaim 366:79.
14 Kovetz Ohr Yisroel vol. 23-33; Divrei Yatziv 2:173:6.
15 Shulchan Oruch, Orach Chaim 382:1.
16 Shulchan Oruch, Orach Chaim 528:1; Mishna Brurah 1.
17 Shulchan Oruch, Orach Chaim 477:4.
18 Shulchan Oruch, Orach Chaim 527.
19 Shulchan Oruch, Orach Chaim 364:3; B’or Halacha.
20 Igros Moshe, Orach Chaim, Aleph 141.
21 Bikkurei Halacha al Tosefes Shabbos 2:13-17.
22 Gemara Shabbos 22:1.