Jewish law still sanctions Jews who deliberately harm other Jews. Why has the community become so reluctant to consider that authority when the harm threatens thousands or millions?
In 1656, the Jewish community of Amsterdam excommunicated a 23-year-old philosopher named Baruch Spinoza (1632–1677). Its leaders pronounced a devastating herem, a religious ban that severed him from communal Jewish life. Members were forbidden to associate with him, speak with him or read his writings. The condemnation became one of the most famous excommunications in Jewish history.
For centuries, Jewish communities disciplined members whose conduct threatened religious obligations or communal life. Jewish law developed several levels of sanctions, most notably nidui and herem.
Nidui was the lesser punishment, a form of temporary religious and social ostracism, traditionally lasting 30 days in diaspora (non-Israel) communities. It restricted ordinary social interaction, sometimes requiring others to maintain a distance of four cubits, roughly six feet. Its purpose was to induce repentance and correction of the offending behavior.
Herem was more severe, imposing deeper and potentially indefinite exclusion from communal life. Depending on the circumstances, it could restrict social relationships, commercial dealings and religious participation. In tightly integrated Jewish communities, exclusion could devastate a person’s livelihood and standing in society.
Maimonides, the Rambam (1138–1204), enumerated 24 grounds for nidui in his Mishneh Torah. They included maintaining dangerous conditions, such as a vicious dog or unstable ladder; refusing to obey a religious court; and preventing the public from performing a commandment.
That last provision is particularly important. Jewish law recognized that obstructing a community’s religious obligations could warrant religious discipline.
These sanctions remain part of modern Jewish life. Orthodox communities still employ religious and social pressure against husbands who refuse to grant their wives a get, the Jewish divorce document required for remarriage under Jewish law. When a rabbinical court determines that a husband must grant a get and he refuses, communal measures may include exclusion from synagogue honors, religious gatherings and other forms of participation. Depending on the circumstances, formal nidui or herem may also be considered.
The Organization for the Resolution of Agunot (ORA) organizes communal pressure against recalcitrant spouses, including public demonstrations and campaigns encouraging synagogues to impose restrictions, with appropriate rabbinic authorization.
Jewish communities recognize that one Jew’s deliberate conduct can cause another such serious harm that communal intervention becomes necessary. Yet these sanctions are rarely discussed when the threatened harm extends beyond an individual to an entire Jewish community.
A husband who refuses a get may face public ostracism for trapping one woman in a marriage. What of a Jew who deliberately works to prohibit circumcision, obstruct synagogue security or prevent entire communities from fulfilling religious commandments?
Three fundamental obligations provide a framework: protecting Jewish lives, preserving religious observance and sustaining Jewish communal continuity.
Protecting Jewish Lives
Jewish law places the preservation of human life, pikuach nefesh, above almost every other religious obligation. Leviticus commands, “Do not stand idly by the blood of your neighbor.” The Talmud extends this principle into an affirmative obligation to rescue someone facing danger.
The clearest case involves a Jew knowingly facilitating violence against other Jews or deliberately obstructing their rescue from an immediate threat. Such conduct directly violates the obligation to protect human life and demands serious religious and communal accountability.
Consider a person deliberately sabotaging essential security at a synagogue or yeshiva facing credible threats. Jewish institutions increasingly depend on trained guards, controlled entrances and protective infrastructure. Knowingly interfering with necessary safeguards could expose worshippers and children to foreseeable danger.
A related question arises when someone campaigns to eliminate protective buffer zones around synagogue or school entrances. Where violent intimidation or obstruction threatens access, removing necessary security measures could endanger the community.
The issue becomes more complicated when the discussion moves to Israel’s national defense. Israeli missile-defense systems, including Iron Dome, David’s Sling and Arrow, protect civilians against incoming rockets and missiles. Campaigning to eliminate essential defensive capabilities without adequate alternatives could foreseeably increase the danger to millions of people.
Broader opposition to American military assistance to Israel presents a less direct case. Military assistance encompasses different weapons, defensive systems and strategic objectives. A Jew who advocates eliminating defensive funding despite a demonstrated threat raises different questions from someone disputing a particular military appropriation.
Jewish law has long required Jews to address threats to human life. Religious authorities should be prepared to examine whether deliberately undermining essential security, whether at a synagogue or across Israel, violates that obligation.
Protecting Jewish Religious Observance
A Jewish community can endure poverty, exile and political upheaval while preserving its identity through religious practice. The covenant of circumcision, the laws of kashrut, prayer, Torah study and communal institutions have sustained Jewish life across generations.
Maimonides explicitly includes preventing the public from fulfilling a commandment among the grounds for nidui. This provides a classical foundation for examining deliberate interference with Jewish observance.
Consider a Jew actively working to outlaw brit milah, the covenant established with Abraham. A successful prohibition would directly prevent Jews from performing one of their foundational commandments. A campaign specifically intended to achieve that result should invite serious halachic examination.
A campaign to prohibit kosher slaughter, shechita, presents a similar concern. Such a law would prevent traditional ritual slaughter within the jurisdiction and could make religious observance substantially more difficult.
The same questions arise when Jews advocate prohibitions on synagogue worship, Torah education or the construction of religious facilities such as mikvaot. Restrictions on kippot and other religious clothing can also interfere with Jewish practice, depending on their scope.
These are precisely the kinds of conflicts in which religious authorities should examine whether conduct constitutes the deliberate obstruction of commandments. Where a recognized court determines that a violation warrants nidui, continued defiance may raise the question of stronger sanctions under Jewish law.
Further along the spectrum lies the controversy over government funding for yeshivas. Some advocates want public funding conditioned on students meeting secular educational standards in English and mathematics. Such requirements may create financial pressure on religious schools, while educational oversight also serves legitimate public purposes.
Jewish law must distinguish legitimate public oversight from deliberate obstruction of religious commandments. Where that boundary is crossed, religious authorities should be prepared to act.
Protecting Jewish Communal Continuity
The Jewish connection to the Land of Israel is integral to Judaism. Jerusalem occupies a central place in Jewish prayer, religious memory and law. Nachmanides, the Ramban (1194–1270), regarded settling the Land of Israel as a positive biblical commandment, although later authorities have debated its precise scope and application.
Consider a Jew advocating a prohibition on Jewish immigration to Israel. Such a restriction would interfere with the ability of Jews to settle in their ancestral homeland, an act that major halachic authorities regard as religiously significant.
Preventing Jews from visiting or praying at their holy sites raises related questions about religious access and worship. Restrictions on Jewish homeownership introduce another dimension, particularly where they specifically target Jewish purchasers.
These concerns are already entering American legislation. In October 2026, Representative Joaquin Castro introduced the Stop the Settlements Act, backed by dozens of Democratic lawmakers. The bill would impose sanctions on certain foreign persons involved in “settlement” activities and prohibit imports from covered settlements. Its reference to the West Bank raises a disturbing question: Would eastern Jerusalem, including the Jewish Quarter of the Old City, fall within its reach?
If so, Jewish organizations involved in purchasing and renovating homes, restoring historic synagogues such as Tiferet Yisrael, or supporting archaeological projects at the City of David could face sanctions-related consequences. The bill leaves critical questions about its application to these activities unresolved. Its sponsors should be required to explain whether Jewish religious and communal institutions in Jerusalem could become targets.
The possibility that American Jewish lawmakers would support legislation reaching Jewish religious institutions in Jerusalem is extraordinary. If Jews knowingly work to obstruct other Jews from maintaining synagogues, owning homes or fulfilling religious obligations in Jerusalem, why should their conduct escape the scrutiny of Jewish law?
Further along the spectrum are efforts to boycott Israeli universities, exclude Israeli rabbis or educators, or discourage purchases of Israeli goods. Such actions may weaken educational, economic and communal relationships, although their connection to established grounds for nidui is less direct.
The case for religious sanctions is strongest where conduct directly obstructs an identifiable commandment or violates another established halachic obligation.
From Nidui to Herem
Jewish communities have historically imposed sanctions on individuals and movements. In 1772, rabbinic authorities associated with the Vilna Gaon (1720–1797) supported bans against the emerging Hasidic movement, a precedent that also illustrates the danger of communal authorities misjudging religious differences. Today, institutions such as Hillel restrict partnerships with organizations supporting BDS such as Jewish Voice for Peace, while the Conference of Presidents rejected J Street’s membership application in 2014. Between silence and herem lies a range of communal measures, from public censure to restrictions on institutional membership and leadership. These measures require clear standards and responsible authority.
The Jewish community is fraying. Its religious institutions, security and connection to Israel face growing internal conflict. Jewish law already recognizes that deliberate harm to another Jew can warrant communal sanctions. Qualified religious leaders should be prepared to examine serious violations, distinguish them from political disagreement and apply appropriate measures where justified.
If Jewish law can sanction a man for trapping one Jewish woman in a marriage, how can Jewish leadership refuse even to consider sanctions against those who deliberately endanger Jewish communities or obstruct their commandments?















































