QUESTION: The Mishnah teaches that an oath to annul a Mitzvah is a Shevu'as Shav. For example, one who deliberately swears not to make a Sukah or to hold a Lulav is punished with Malkus for making a Shevu'as Shav.
The Gemara earlier (25a) gives another example of a Shevu'as Shav. Rebbi Yochanan says that one who swears, "I will not sleep for three days," is punished with Malkus and may sleep immediately. RASHI (25a, DH Malkin) explains that he receives Malkus for making a Shevu'as Shav because it is physically impossible to go three days without sleep.
Does the same law apply to a person who swears that he will not eat for a period of time for which it is not possible to fast without starving? Is such a Shevu'ah similar to a Shevu'ah not sleep for three days, or is it different, because it is physically possible to abstain from food indefinitely (even though doing so will lead to death by starvation), and thus the Shevu'ah takes effect (and when he reaches the point at which his life is in danger, he will be permitted to eat in order to save his life)?
(a) The RAMBAM (Hilchos Shevu'os 1:7) compares a Shevu'ah not to eat for seven consecutive days to a Shevu'ah not sleep for three days. Neither Shevu'ah is valid because of the practical impossibility to fulfill it. Both Shevu'os have the status of a Shevu'as Shav, and if one deliberately makes such a Shevu'ah he is liable for Malkus. The Rambam also writes (5:20) that one who swears not to eat for seven days may eat right away, because the Shevu'ah does not take effect.
(b) The RAN (10a of the pages of the Rif) discusses a Shevu'ah not to eat for one month. He asserts that such a Shevu'ah is not similar to a Shevu'ah not to sleep for three days. The latter Shevu'ah does not apply at all, because during the course of three days he inevitably will fall asleep at some point, even against his will. In contrast, a Shevu'ah not to eat for a month is physically possible to fulfill. The Halachah states that when his situation becomes life-threatening, the concern for Piku'ach Nefesh overrides the prohibition against violating one's Shevu'ah. Since the Shevu'ah takes effect, however, he may not eat more than what is necessary for survival.
The Ran writes that when one makes a Shevu'ah to injure himself, the Shevu'ah takes effect. Although the Torah forbids a person from injuring himself, the prohibition is not stated explicitly but is derived from a verse. (See Bava Kama 91b, where the Gemara derives the prohibition from Bamidbar 6:11, which discusses a Nazir who afflicts himself.) The Ran understands that a Shevu'ah takes effect on a prohibition which is not stated explicitly in the Torah. Therefore, the person who makes such a Shevu'ah is not be allowed to injure himself, and would have to bring a Korban for transgressing the Shevu'ah.
In contrast, a Shevu'ah to kill himself does not take effect, because suicide is explicitly forbidden by the Torah: "However, your blood of your souls I will demand (if you take your own blood)" (Bereishis 9:5). The Ran cites an additional source in the Torah which forbids suicide: "Be careful and guard your soul very carefully" (Devarim 4:9).
The RAN cites the words of the Rambam, and -- although he disagrees with the Rambam's comparison of the two Shevu'os -- he concludes that the Rambam's ruling is correct, for a different reason. The Ran explains that a Shevu'ah not to eat is invalid because it constitutes a Shevu'ah to transgress a Torah law; it effectively is a Shevu'ah to kill himself. For this reason it is a Shevu'as Shav.
The Ran concludes, like the Rambam, that if one swears not to eat for seven days, the Shevu'ah does not take effect because it is a Shevu'ah to transgress a Torah law. He receives Malkus for making a Shevu'as Shav, and he may eat immediately.
(See also MINCHAS CHINUCH (30:3) who writes that he is not aware of the source for the Rambam's statement that one cannot survive seven days without eating or drinking at all. He concludes that the Rambam must have known this from his knowledge of medical science. See a possible source in Sanhedrin 108b, and RASHI there, DH Lo Batzir.) (D. BLOOM)


QUESTIONS: The Gemara (29a) cites a Beraisa that discusses the oath to observe the laws of the Torah, which Moshe Rabeinu made the Jewish people make. He said to them, "Know that I am making you swear not according to your own Da'as (understanding of the Torah), but rather according to the Da'as of Hash-m and according to my Da'as."
The Gemara explains that the reason why Moshe Rabeinu said both "Hash-m's Da'as" and "my Da'as" was in order to prevent the possibility of annulling this Shevu'ah. RASHI (29b DH Ela) explains that since the oath was based on the Da'as of Hash-m and Moshe, it was considered an oath made according to the Da'as of the Rabim (public) which cannot be annulled (see Gitin 36a).
The Gemara implies that when a community decrees a Cherem (a public proclamation which all members of the community are obligated to follow) "according to the Da'as of Hash-m and the Da'as of the community," it is binding and cannot be annulled. (An example of such a proclamation is found in the SHULCHAN ARUCH YD 1:11, who mentions a community that decreed a Cherem that only a certain Shochet may slaughter meat. Another Shochet transgressed the Cherem, and some authorities ruled that the meat of the second Shochet is forbidden.) TOSFOS (DH Ki) asks that it is common practice to retract such public Charamos, but according to the Gemara here it should be impossible to retract such Charamos. Even if the Cherem is made only "according to the Da'as of the community," it is an oath made according to the Da'as of the Rabim which cannot annulled. Tosfos asks further that the annulment of an oath may be done only with Charatah, an expression of regret for having made the oath. What Charatah is the basis for the annulment of public Charamos?
(a) TOSFOS answers that a public Cherem is different in that the original Da'as of the community was that the Cherem will be annulled whenever the community desires to annul it, and that such annulment may be done without Charatah.
Tosfos adds that although the Cherem was made "according to the Da'as of Hash-m," this does not mean that it is an oath made according the Da'as of the Rabim. Rather, this is merely a term that the Ge'onim instituted in order for people to take the Cherem seriously.
Tosfos writes that this is not similar to the oath that Moshe Rabeinu made the Jewish people take. Hash-m told Moshe to make them take that oath. In contrast, the Charamos made by the community depend solely on the public's decision to institute such policies.
(b) The ROSH explains that the reason why the conditions necessary to annul an oath (such as Charatah, and an expert Chacham, or three ordinary people) are not required for the annulment of a public Cherem is that such a Cherem does not possess the status of a Neder. Rather, it is a type of decree or excommunication that anyone who transgresses the Cherem will be separated from the community. (For example, no one may speak or do business with the person who transgresses the Cherem.) It is a process of Niduy which the community may apply, and annul, at will.
The KEHILOS YAKOV in Moed Katan (#4) points out that, apparently, Tosfos maintains that a public Cherem does have the status of a Neder; the Neder, however, is made dependent on public opinion. In contrast, according to the Rosh, a Cherem does not have the status of a Neder at all. Even if is made with the "Da'as Rabim," it still may be annulled without Charatah.
An example of a Cherem which forbids an act which otherwise would be permitted is the Cherem of Rabeinu Gershom against marrying more than one wife.
The Kehilos Yakov writes that many Rishonim imply that when a person performs the act which is prohibited by the Cherem, he not only is punished and cursed, but his very act constitutes a transgression. This is the view of Tosfos here, who considers the Cherem to have the status of a Neder or Shevu'ah. One who transgresses the Cherem is considered as though he transgresses a Neder or Shevu'ah.
In contrast, the Rosh maintains that one who performs the act prohibited by the Cherem has transgressed no prohibition per se, because the Cherem does not have the status of a Neder but is merely a decree on the community. There is no actual prohibition on the act that the Cherem proscribes. Rather, the Cherem imposes a penalty on a person who disregards the Cherem.
The Kehilos Yakov adds that the Rosh apparently maintains that that it is not possible to place a prohibition of a Neder on someone else. Accordingly, the Cherem of the community is merely a decree of punishment upon anyone who does not conform with the ban. (D. BLOOM)