Mishneh Torah, Vows 1-3

Sugya Map

• Issue: Defining the boundaries of Nedarim—what constitutes a valid "handle" (yad) for a vow versus a statement lacking the legal capacity to create a prohibition.
• Nafka Mina: Whether a person is liable for malkot (lashes) or obligated to bring a korban based on his verbal pledge.
• Primary Sources: Mishneh Torah, Hilchot Nedarim 1:1–1:11; Nedarim 2a–15a.

Text Snapshot

Rambam, Hilchot Nedarim 1:1: "The intent of a vow is not to forbid what the Torah has prohibited... but to cause permitted entities to become forbidden to him."

• Nuance: The Rambam emphasizes the distinction between hefetz (the object) and gavra (the person). A vow acts upon the hefetz, rendering it, in effect, like a korban to the utterer.

Readings

• Radbaz (1:1): Explains that a vow requires the object to be inherently permitted. If one attempts to vow upon nevelot (carrion), the vow is void because the object is already forbidden by Torah law—one cannot add a neder to an existing issur (a "prohibition upon a prohibition").
• Ramban (Sefer HaMitzvot, Mitzvah 94): Disagrees with Rambam regarding the count of the positive commandment to fulfill one's word, arguing that vows of prohibition and vows of sanctification constitute two distinct mitzvot, not one.

Friction

• Kushya: If a vow functions by equating a mundane object to a korban, why does a vow upon terumah not take effect? Both appear to involve a form of sanctity.
• Terutz: As Rambam (1:11) suggests, terumah is already "bound" to the priest and lacks the nature of a voluntary pledge. A vow is effective only when the subject can be endowed with status by the speaker; since terumah is mandatory, it is not subject to the "equation" of the vower.

Intertext

• Numbers 30:3: "To cause a prohibition to take effect upon his soul."
• Shulchan Aruch, Yoreh De'ah 207:1: Codifies the Rambam’s principle that we follow the local vernacular, affirming that the intention of the speaker is the primary engine of the neder.

Psak/Practice

The overarching heuristic is Yadot Nedarim Ke-Nedarim ("Handles of vows are as vows"). If the intent is clear, the specific terminology is secondary to the functional prohibition created. In modern practice, this necessitates extreme caution: imprecise, "lighthearted" speech regarding one's property or habits can create binding halachic prohibitions.

Takeaway

A neder is not mere speech; it is a creative act of halachic ownership that transforms mundane reality into sacredly forbidden space. If you cannot make it holy, you cannot make it forbidden.