Dov Lerner on Yeshiva University Museum's Eruv Exhibition Shabbat is designed to be a day of rest, relaxation and communal prayer. Due to halakhic restrictions on their carrying items from one place to another, however, observant Jews can become prisoners in their own homes. The rabbis, therefore, wherever they could, came up with a way to circumvent this issue: the eruv. The word literally means “mixture”; and views on the eruv are themselves mixed and hotly debated. The Yeshiva University Museum now has an exhibition devoted to the eruv called, “It’s a Thin Line: The Eruv and Jewish Community in New York and Beyond.” The museum launched the exhibition with a day-long symposium reflecting the debates that the eruv has occasioned. Among the Sabbath laws is an injunction against transferring an object from a private to a public space or moving it within the public space itself. The prohibited activity is often simply called "carrying." The activity is heavily regulated, and the rules are complex. Halakhic literatures are occupied by questions of how to define a public or private space and what constitutes a transfer. For purposes of this idea of “carrying,” the rabbinic discussions generally identify four types of space: reshut harabim, or public space; reshut hayahid, or private space; makom patur, an exempt area; and karmelit, related to the word for “garden,” which is legislatively treated as a kind of limbo, a public space that nevertheless has some characteristics of private space.  The karmelit is the only space around which the construction of an eruv is permitted. The eruv’s artificial architecture—often consisting merely of poles and wires—defines the confines of the space as private and, thus, allows carrying within its bounds. Nowadays, it is not unusual for an area with a large Jewish population have an eruv. Manhattan's eruv covers over half of the island, stretching from Harlem in the north to Greenwich Village in the south. In recent years eruvim have sprung up in cities across the globe, from San Diego to Vienna. But the halakhic legality of the contemporary eruv is not universally accepted. Though many observant Jews embrace the eruv, a large swathe of Orthodox Jewry will not use it. Yeshiva University Museum’s inaugural symposium, titled “The Mystery and History of the Eruv,” covered the history of the eruv fairly quickly. In a presentation on the theoretical basis of the eruv, Lawrence Schiffman described the fierce debate over the device between ancient Jewish sects—the Sadducees, who rejected the entire eruv project, and the Pharisees who promoted the eruv’s use. Charlotte Fonrobert addressed the practical application of the eruv in a more recent context, describing its use, championed by Rabbi Selig Bamberger, in 19th century Würzburg, Germany. Jeffrey Gurock brought the discussion rapidly into the present time, analyzing controversies over the eruv in 20th century Manhattan. The demographic that now depends on the eruv, he said, consists of what may be called "eruv moms"—because mothers with young children are often the primary victims of an area with no eruv. While their husbands attend synagogue on the Sabbath, they are stuck indoors. Forbidden from transferring their children outside their private homes or shouldering their weight in the streets, they suffer from the inevitable result: Sabbath cabin-fever. The eruv allows mothers and their young children to join the congregation. In the afternoon, the symposium turned to the future. There were pragmatic projections of eruv building, in which Elliot Malkin proposed replacing wires with lasers and weekly checkers with cameras. Isaac Cohen made sociological observations about the ways of making Jewish space. The final speaker, author and law professor Thane Rosenbaum, examined the philosophical implications of the different notions of Jewish private and public spaces, touching on the question of what it means, as a Jew, to be an insider or an outsider. The new exhibition itself builds on Rosenbaum's theme, exploring the role the eruv plays within American Jewish culture and the ways in which that role differs from the eruv’s historical function. At the entry to the exhibit, one is greeted by a wall of images and biblical quotes that express and emphasize the restriction on Sabbath “carrying.” Then, before visitors are presented with any details of the ways in which the rabbis circumvented this restriction, they are offered the primary Jewish proof of the necessity of such circumvention—not mothers with babies but hot cholent. In pre-modern Europe, Jews did not have private ovens. Individual families warmed their Sabbath lunches in a common place: the premises of the local baker. The eruv provided the mechanism that allowed them to carry their cholent home. Breaking from the historical background, the exhibit, escorting visitors with a vertical wire tied taut above their heads, introduces the subject of the Manhattan eruv.  The exhibit begins with some of the oldest disagreements and earliest designs, then proceeds through the evolution of the eruv to date.  Where the exhibition excels is in giving a sense of the social impact of an eruv, running televised interviews with rabbis and builders and including Wyatt Cenac's wry segment on the Daily Show describing the effort to prevent the construction of an eruv in the Hamptons—an effort led by secular Jews seeking to keep the Orthodox out. At the exhibit’s end, visitors are met by a wall of different quotes that attempt to make them confront the profound implications of the boundaries of private space. The quotes are not talmudic or rabbinic, neither biblical nor historic. Instead, they represent the voices of current residents of Teaneck and Great Neck, Passaic, and Queens, all remarking on the ways in which an eruv has changed their lives—by freeing the otherwise fastened, allowing the infirm and elderly, as well as mothers and children, to experience the Sabbath world outside their homes. When an eruv is built, they say, synagogues become accessible and friends closer. Perhaps not so ironically, an eruv, by enclosing a space, unchains the immobile and breaks down walls. Dov Lerner is a Tikvah Fellow. For the past two years he has been a rabbinic intern at Lincoln Square Synagogue. He is in his final year of studies toward rabbinic ordination at Yeshiva University's Rabbi Isaac Elchanan Theological Seminary. Reprinted with permission from Jewish Ideas Daily.