Let’s take a brief walking tour of the Yale Eruv. Start at the intersection of Orchard and Henry streets. From there, follow the northern border of the Yale Eruv along Henry until it meets Winchester Avenue. After three blocks, switch to Sheffield Street and make a sharp right turn at Huntington, just across from Albertus Magnus College. After that, your path traces the boundary of East Rock Park, cutting down Whitney to the gentle curve of Cold Spring Street and Mitchell Drive.

Mitchell turns into Nash, and Nash to State Street. At this point, you will want to follow Edwards Street to Orange — due to the unfortunate placement of a telephone pole, both sides of State are outside the Eruv. So is the block of Orange Street between Bradley and Trumbull. After a brief detour on Whitney, follow the inner edge of State Street down to North Frontage Road. From there, keep due west on Park Street to include Yale New Haven Hospital, and then back up along South Frontage, until the Yale Eruv meets the separately-maintained New Haven Eruv back at Orchard Street.

The globby, vaguely rectangular space we’ve just traced out is a private courtyard for the purpose of Jewish law. Six days out of seven, it’s irrelevant, but on Shabbat, it becomes essential. One of the types of work forbidden on the Sabbath is carrying from one domain to another — from the public street, for example, into a private home. The Eruv allows observant Jews who live within its boundaries to carry things — keys, food, toddlers — on their day of rest, because the area it encloses constitutes a single, private domain.

The legal concept of the Eruv developed to cover the case of multiple families whose homes opened onto a shared courtyard. By dedicating a food item as a symbolic communal meal — most modern Eruvim use matzah, the dry crackers which Jews eat on Passover, and which are probably left over from Passover — the families could legally designate their complex as a single, shared home. Fairly reasonable stuff.

Of course, scaling up this neighborly arrangement in size presents certain legal challenges. For one thing, the whole area must be enclosed by walls, however loosely defined. In its most basic form, a legal wall consists of a vertical post, which must be directly under, though it need not support, a horizontal lintel. Most modern Eruvim, including Yale’s, use telephone wires as their lintels. Since wires usually extend from the sides of utility poles, instead of reaching over the top, additional wood or rubber vertical post must be attached to the poles beneath them. Gaps in the telephone wires are supplemented with fishing wire. Each open space in the resulting “wall” is, technically, a “door.”

You’d be forgiven for thinking that the logic here holds up only slightly better than a monofilament lintel. Eruvim are among the more finicky areas of Jewish law. Disputes about the validity of a given Eruv are common, and a few authorities oppose the practice altogether. Even secular Jews tend to associate them with religious hypocrisy. (A passage in Kafka’s diary: “The telephone and telegraph wires in Warsaw are, through bribes, supplemented so that they form a complete circle, which turns a city into an enclosed area in the sense of the Talmud, like a courtyard, so that even the most pious can move within this circle on Saturday carrying odds and ends like handkerchiefs.” Enclosure, in Kafka’s claustrophobic world, is never a good sign, but the bribery is more telling.)

Despite the controversy surrounding Eruvim, most large observant Jewish communities have one. They’re especially necessary for families with young children, explains Shlomo Zuckier GRD’19, an associate rabbi at the Slifka center and co-director of the Jewish Learning Initiative on Campus.

“The worst scenario — and it’s actually a very common one — is that the family can’t go anywhere, because the children can’t walk. What usually happens in orthodox communities is that the mother stays home on the Sabbath, which isn’t an enjoyable thing,” Zuckier says. The Eruv allows parents to bring their children to synagogue, or to visit family and friends. It also obviates the complicated legal status of wheelchairs and walkers. By facilitating movement within its borders, the Eruv helps create a real communal space.

Jason Rappoport, a former associate rabbi at the Slifka Center, spearheaded the development of the Yale Eruv with the aid of several members of the community — including Sharon Reinhart, an instructor at the Yale School of Drama. “It was a many year process,” Reinhardt told me. And while building an Eruv is ritually complex, most of the challenges were regulatory.

One of the most difficult legal challenges to overcome was the requirement that the community responsible for maintaining the Eruv have some legal right to the space it covers. In a predominantly gentile community, these rights can be difficult to secure.

“Generally people go through the mayor’s office for that,” Reinhart explained, “which was what we tried to do, but it was pretty soon after a Supreme Court case where a town in Connecticut was using eminent domain to take people’s property … when we mentioned to the people in the mayor’s office that the thing that gave them the standing to help us was eminent domain, they were all kind of touchy about it.” The mayor’s office wasn’t able to help with the portions of the Eruv that overlap with Yale’s campus, since Yale’s charter predates the city charter.

In the end, the Eruv builders were able to secure the necessary permissions from the New Haven Police Department. This is another common solution to the land use problem. Because the police have the right to enter any building in New Haven, even if only in an emergency situation, they can “rent” part of the city to the group responsible for maintaining the Eruv.

The actual construction of the Eruv presented additional challenges. “There were some issues with the city as well vis-a-vis the street where there’s no utility poles,” Reinhart said. “They wanted to put the poles underground, we wanted to put things up, they were not thrilled.” Modifying the poles to fulfill ritual requirements required more negotiations with utility companies. “Some things had to go through the Board of Alders, the city engineering department, the traffic department — everyone wanted to get on it. There were a lot of meetings. And those meetings were a prerequisite to doing any kind of work.”

The Yale Eruv was completed in 2007 after years of effort. The symbolic box of matzah is still on a shelf in Slifka’s library (it has been rumored, but never confirmed, that this matzah has been replaced at some point in the past decade). Every week, a volunteer checks the walls for missing posts or fallen wires. The arrangement is unobtrusive — some fishing wire here, a wooden post there — but not particularly weather-resistant. Without flags marking the wires, making them easier for the checkers to spot, the whole apparatus could easily go unnoticed.

The Yale/New Haven Eruv’s website features detailed instructions for just this eventuality. “Stay on the south side of Henry, and circle south around both poles,” it warns. “Do not walk along Legion/South Frontage when crossing from one Eruv to the other. The Eruv narrows to the point that you’d have to press yourself against a fence and wriggle along.”

Observant Jews at Yale have to live without the Eruv for at least a couple weeks a year, usually in winter, when heavy winds or snows bring down a wire or two. A single missing section can invalidate the whole structure. During those weeks, every trip past one’s own front door requires planning. Where should I leave my things before sunset? What’s the best way of incorporating a key into a garment? (Some people own specialized key belts, but I prefer lacing them into my shoes).

Living without an Eruv — rather like living with an Eruv, and for that matter, the whole of institutional Jewish practice — is a perpetual exercise in attention to detail. That might be why I’ve never thought of the Eruv as a cheat. Ignoring a rule is one thing. But to develop, over the course of 2,000 years, a legal workaround of such immense complexity, requiring years of persistence and constant supervision, all in the name of making people’s lives a bit easier, is almost sublime.

Contact Clara Collier at

clara.collier@yale.edu .