Massekhet Nedarim is connected with a number of other Talmudic tractates, including Nazir, Shevuot and Arakhin. The similarity among these tractates is that all of them deal with obligations that are not imposed by the Torah, but are voluntarily created by an individual. On one level, Nedarim is a general category of oaths that encompasses all of the other cases. Interestingly, while Massekhet Nazir follows Nedarim in Seder Nashim, Shevuot is in Seder Nezikin and Arakhin is in Ḳodashim. Although Nedarim focuses on a narrow set of laws, it is placed in Seder Nashim because the biblical source deals with vows made by women (see Bamidbar 30:3), even though the tractate deals with all types of vows.
Although the most common use of the term neder in the Bible is in the context of nidrei hekdesh (vows of consecration – donations to the Temple such as sacrifices), in rabbinic literature it is used most often for nidrei issur – vows of prohibition, when a person forbids himself (or others) from deriving benefit from something. While these two categories are certainly different, a proper understanding of nidrei issur is dependent on understanding nidrei hekdesh. When a person takes an ordinary object and sets it aside for the Temple, by sanctifying it he essentially is removing it from everyday, mundane use. Similarly, when a person establishes that he will not derive benefit from a specific object he is removing it from his use; when he establishes that an object that he owns will be forbidden for another person, he is limiting the prohibition to a specific person (or group of people).
Although there is no mitzva that commands a person to take a neder, once a person takes a vow he is obligated by the Torah to fulfill it if it was a positive commitment and forbidden by the Torah to break it if it was a statement of prohibition (see Bamidbar 30:3). A person who does not keep his vow is subject to penalties as related in the Torah. Once a person has expressed his idea as a statement, it is no longer a private commitment, but a Torah obligation.
A number of basic requirements for a neder to take effect include the need for a person to have clear intent, that he express it in a clear manner and that the neder refers to a specific object. Without these three elements, the neder will not take effect, (as least not on a biblical level). Much of our tractate deals with clarification of these conditions.
Although the source for the laws of nedarim is from the Torah, generally speaking, the Sages took a dim view of taking vows. This is based on the passage in Kohelet (5:4) “Better not to vow than to vow and not to pay” as well as the fact that people often took vows because of anger or arguments. Furthermore, the Sages did not encourage people to accept upon themselves more prohibitions than the ones obligated by the Torah. For this reason, the Sages recommended that a person who took a vow should try to be matir neder – find a way to have the vow annulled or dissolved. The concept of hatarat nedarim has no biblical source – the expression used by the Sages to describe their source is that they “float in the air” without any visible means of support (see Hagiga, daf 10a) – but the idea stems from the basis of nedarim in and of themselves. Since a neder is predicated on the intent of a person, once a person has decided that he does not wish to be obligated by the neder, it should “expire” and lose all significance. Nevertheless, since a person cannot make such a decision on his own, he must turn to the court or to a Rabbinic sage who can arrange to be matir neder. This hatarah takes place in one of two ways:
- By use of a petah – an opening – where in the course of discussing the neder, the question is raised as to whether the person understood the consequences and implications of the vow when it was first made. If he can say that he did not, the sage or the court can abrogate the neder.
- By use of haratah – a statement of regret. Under certain circumstances, when the person who takes a vow states that he is sorry that he ever made this neder, the sage can annul the vow, and we treat it as though it had never taken effect.
A related law that does appear in the Torah is hafarat ha-neder. The Torah gives the authority to the father of a single girl or the husband of a married woman to nullify a vow made by the daughter or wife at the time that it first comes to the attention of the father or the husband. This power is limited in a number of ways, e.g. it can only be done in cases where the vow will affect the relationship between them.