Nedarim - Daf 15
- The case of קונם שאני בשינה in the Mishnah
Rav Yehudah said on Daf 14b that when one says: קונם עיני בשינה היום אם אישן למחר – “my eyes are konam for sleep today if I sleep tomorrow,” we do not allow the person to sleep today, since he may sleep tomorrow and trigger the neder. The Gemara here poses a challenge from our Mishnah, which states that: If one says: קונם שאני בשינה – “konam on my sleep,” he is prohibited by לא יחל דברו, he shall not desecrate his word. After clarifying that a neder expressed this way could not be valid, for we have learned that a neder is not effective on activities, but only on tangible entities, and that the neder must have a time limitation, since a neder is also invalid like a shevuah if it is impossible to keep, the Gemara concludes that the Mishnah must be where he said: קונם עיני בשינה היום אם אישן למחר, - “my eyes are konam for sleep today if I sleep tomorrow.” This indicates that he was allowed to sleep on the first day, which is how he violates לא יחל retroactively when he sleeps the next day. The Gemara first answers, that although we do not allow him to sleep on the first day, the Mishnah is teaching the halachah of one who does. Alternatively, Ravina answers that the Mishnah is speaking of someone who simply said קונם שאני בשינה - “konam on my sleep,” without referencing his eyes. Although the neder is not valid because sleep is intangible, מדרבנן it is an effective neder and he is still subject to לא יחל דברו.
- שאת נהנית לי עד הפסח אם תלכי לבית אביך עד החג
The Gemara challenges Rav Yehudah again from a Mishnah, which states that if one says to his wife,שאת נהנית לי עד הפסח אם תלכי לבית אביך עד החג – “that which you benefit from me is forbidden until Pesach, if you go to your father’s house from now until Succos,” הלכה לפני הפסח אסורה בהנאתו עד הפסח - if she went before Pesach, then she is forbidden in his benefits until Pesach. The Gemara infers that if she has not yet gone, she may still benefit from her husband, and we are not concerned that she will go to her father’s house before Succos and trigger her neder. The Gemara answers: הלכה לפני הפסח אסורה ולוקה - if she went before Pesach, she is prohibited from benefiting from her husband and receives malkos if she does. לא הלכה אסורה בעלמא - if she did not go, she is merely forbidden Rabbinically to benefit from her husband, out of fear that she may go to her father’s house before Succos.
- How a neder on marital relations can be effective
The Mishnah on Daf 14b had said that one who says to his wife: קונם שאני משמשך – “konam my relations with you,” the neder is effective. The Gemara here asks: והא משתעבד לה מדאורייתא - but he is Biblically obligated to her, as it is written, שארה כסותה ועונתה לא יגרע - her food, her clothing, and her “time,” referring to marital relations, he cannot reduce. How then can the neder take effect? The Gemara explains that he saidהנאת תשמישך עלי – “the benefit of your relations is forbidden upon me,” in which case the neder is effective, although he effectively forbids her in having relations with him. The Ran explains that he is able to prohibit his own benefit, which is in his control, because he is not directly prohibiting her benefit. This distinction is borne out from a statement of Rav Kahana, who said if a woman says: תשמישי עליך כופין אותה ומשמשתו – “my relations are forbidden upon you,” we force her to have relations with him, דשעבודי משעבדת ליה - because she is obligated to him, and therefore the neder cannot take effect. But if she said:הנאת תשמישך עלי – “the benefit of your relations is forbidden upon me,” it is forbidden, שאין מאכילין לו לאדם דבר האסור לו - because we do not feed a person that which is forbidden to him.
