דברים, פרק כ״ג, פסוק ז׳

The complete and eternal severing of ties with the nations of Ammon and Moab represents a unique exception in the foreign relations of the Israelites. Despite an ancient family connection, their deliberate betrayal created an unbridgeable divide. Ammon and Moab were descendants of Lot, Abraham's nephew. God originally rewarded Lot for accompanying Abraham by granting his descendants their own land. However, Ammon and Moab chose to break this bond of brotherhood, actively plotting to distance themselves and harm the Israelites with vile schemes [רמב״ן, הטור הארוך, ביאור יש״ר, ביאור שטיינזלץ].

Consequently, the prohibition against seeking their peace serves as a direct measure for measure. Because they refused to greet the Israelites in peace and instead plotted evil [העמק דבר], they must be treated in the exact same manner [בכור שור]. Yet, because they are still family, God did not command an active war of annihilation against them, as He did with the Midianites. Instead, the directive is essentially passive: the Israelites must distance themselves entirely and refrain from doing good to them, without necessarily initiating harm [שד״ל].

The primary approach among commentators views this directive not merely as an emotional response, but as a source for specific legal exceptions. Since the evil actions of Ammon and Moab are already well established, the instruction to avoid seeking their peace or welfare dictates unique rules of engagement [תורה תמימה, מלבי״ם].

In the context of military conflict, this mandate alters the standard laws of war. While the Torah generally requires offering terms of peace before besieging a city, the Israelites are exempt from this requirement when fighting Ammon and Moab, such as in defensive wars or when battling over territories these nations conquered from others [רמב״ן, הטור הארוך, רלב״ג]. Additionally, the standard prohibition against destroying fruit trees during wartime is lifted; in conflicts with Ammon and Moab, trees may be cut down specifically to cause them distress and financial harm [רמב״ן, חזקוני]. However, commentators note certain nuances regarding peaceful interactions. If Ammon and Moab independently seek to make peace, their request may be accepted [תורה תמימה]. There is also an ongoing legal discussion regarding whether an Israelite is permitted to return a simple greeting of peace if approached by an Ammonite or Moabite first [נחל קדומים].

The prohibition against seeking their welfare also affects the laws regarding an escaped slave. Normally, the Torah mandates providing safe haven and good treatment to a slave who flees to the Land of Israel. However, a slave who escapes from Ammon or Moab is excluded from this protection, and there is no obligation to treat him well [רש״י, מזרחי, תורה תמימה, מלבי״ם, ברכת אשר].

To ensure this strict stance is fully understood, the instruction emphasizes its absolute permanence. It is not a temporary measure for the generation in the desert, but an eternal Commandment binding for all time [תורה תמימה, מלבי״ם]. This uncompromising approach is particularly striking when contrasted with the treatment of the Egyptians and the Edomites. Even though those nations also harmed the Israelites and confronted them with violence, they may be accepted into the community after three generations due to past kindnesses and ancient family ties. In stark contrast, the betrayal of Ammon and Moab resulted in them being punished and permanently excluded [רמב״ן, הטור הארוך].