A continuous thread of wire wraps around most of Manhattan, raised up overhead and spanning between periodic posts. Most people don’t notice it at all, but to Orthodox Jewish people of the city, it’s vital. This thread conceptually turns public space into private domain, and allows observers of the Sabbath to carry their essential belongings with them. And every week, a rabbi drives around the island to make sure this 20-mile “eruv” line remains intact for the Jewish Sabbath. Modern eruvs encompass large sections of cities around the world, from Toronto to Tel Aviv. New York City’s extensive winding cable only dates back a few decades in its current form, but the tradition is an ancient one.
Per Lorne Rozovsky, a Jewish lawyer and educator with a special interest in rituals, “the literal meaning of the word is blending or intermingling,” and “the concept of an eruv goes back to the principle of Shabbat rest. Under Jewish law on Shabbat, it is forbidden to carry anything — regardless of its weight, size or purpose — from a ‘private’ domain into a ‘public’ one or vice versa.” To bring even a prayer book and reading glasses to a synagogue, for instance, one’s home and place of worship would need to be in the same “domain.” Today, the same restrictions can apply to things like strollers, canes and wheelchairs, though Rabbinic authorities have gone back and forth on this issue.
In ancient times, walled neighborhoods (or entire cities) could be used to frame eruvs, figuratively extending private spaces into public areas. Of course, walling a modern urban metropolis is not practical (though, for a time, some rabbis argued Manhattan’s sea walls could be sufficient to constitute an eruv). So the question becomes: what does it mean for something to actually be a “wall” as such?
“A wall can be a wall even if it has many doorways creating large open spaces,” writes Rozovsky. “This means that a wall does not have to be solid.” By extension, an eruv can be formed by treating, say, public telephone poles with cables slung between them as minimalist “door frames.” Effectively, this creates a system of “walls” that are entirely made up of doorways. And that is the argument behind NYC’s eruv.
“But a single break in any part of the line voids that symbolic space,” reports Michael Inscoe, who spent a day riding around NYC and checking for breaks with a rabbi. “According to the 100 pages devoted to eruvin in the ancient Talmud, the boundary is only effective when the entire line is intact.” Thus, any disconnect is a serious problem.
Sometimes, utility workers will clip a line, or allow it to drop down, and thus breaking the “door frame.” In other cases, weather or accidents can take down a key pole in the network. Fixing these breaks is usually a simple matter, involving some wire, a cutting tool and maybe a small cherry-picker crane. If the line can’t be repaired in time, an entire eruv is declared void until it can be reconnected. Upkeep in NYC runs around $100,000 a year, but the cost is spread around, shared by Orthodox synagogues across Manhattan.
Eruvs can be controversial, though, even within Jewish communities. Some worry that observant Jewish people living in cities with eruvs will become too accustomed to this symbolic boundary’s permissiveness, or won’t notice when a line is broken. Eruvs have also given rise to lawsuits, particularly when local and religious laws clash.
But “despite these problems, the construction of eruvs continues,” writes Rozovsky, even if it often goes unnoticed. “The Washington, D.C. eruv includes the White House. The Strasbourg eruv includes the European Court of Human Rights.” Eruvs can also be found in and around other large global cities including Amsterdam, Manchester, London, Melbourne, Johannesburg, Gibraltar, Venice, and Vienna.
In many cases, though, they go largely unseen by those who don’t have a vested interest in their existence. Naturally camouflaged in urban environments, eruvs tend to blend in with the messy everyday infrastructure of elevated cables that surrounds and connects us.