Nedarim - Daf 17
- הריני נזיר אם אוכל הריני נזיר אם אוכל
The next Mishnah states : יש נדר בתוך נדר - A neder can take effect during the term of another neder, ואין שבועה בתוך שבועה – but a shevuah cannot take effect within the term of another shevuah. How so? If one says: הריני נזיר אם אוכל הריני נזיר אם אוכל – “I am hereby a nazir if I eat this bread, I am hereby a nazir if I eat this bread,” and he eats it, חייב על כל אחת ואחת – he is chayav to observe a term of nezirus for each and every one of his nedarim. The Ran explains that the second nazir declaration can take effect even while the person is already a nazir, but it does not actively begin until he completes his first nezirus. But if one says: שבועה שלא אוכל שבועה שלא אוכל “ - A shevuah that I will not eat this bread, a shevuah that I will not eat this bread,” and he eats it, אינו חייב אלא אחת- he is only chayav for one violation. The Ran explains that this is based on the principle of אין שבועה חל על השבועה – A shevuah cannot take effect on another shevuah.
- Machlokes if the Mishnah is only in a case of הריני נזיר היום הריני נזיר למחר
The Gemara records a machlokes about the parameters of this halachah. Rav Huna says, לא שנו אלא דאמר הריני נזיר היום הריני נזיר למחר - they only taught this regarding a case where he declared, “I am hereby a nazir today,” and then said, “I am hereby a nazir tomorrow,”דמיגו דקא מיתוסף יומא יתירא חיילא נזירות על נזירות - for since an extra day is added, the second nezirus can take effect upon the first nezirus. Because each nezirus term is thirty days, starting a second nezirus tomorrow would dictate that it is ending one day later than the first. This allows the second nezirus to take effect (although, practically, he cannot begin it until after the first nezirus is completed).אבל אמר הריני נזיר היום הריני נזיר היום - But if he said, “I am hereby a nazir today,” and then said, “I am hereby a nazir today,” אין חלה נזירות על נזירות - the second nezirus cannot take effect upon the first nezirus. Since no extra time is added in the second nezirus, it has no way of taking effect. Shmuel disagrees and says, אפילו אמר הריני נזיר היום הריני נזיר היום - even if he said, “I am hereby a nazir today,” and then said, “I am hereby a nazir today,” חלה נזירות עליה - the second nezirus takes effect upon him. He holds that a second nezirus is able to take effect while he is a nazir, even without adding any time in the second declaration. The Gemara on Daf 18a will provide a Scriptural source for this halachah.
- שבועה שלא אוכל תאנים וחזר ואמר שבועה שלא אוכל תאנים וענבים
The Gemara here seeks to explain how Rav Huna would explain the parallel case of shevuos, since he holds that a second nezirus is only effective where he said, הריני נזיר היום הריני נזיר למחר, and answers it is where he first said, שלא אוכל תאנים- “I swear I will not eat figs,”וחזר ואמר שבועה שלא אוכל תאנים וענבים - and then said, “I swear I will not eat figs and dates,” דלא חיילא - that the second shevuah does not take effect. The Ran explains (in his preferred explanation) that the second shevuah means to specifically prohibit eating both figs and grapes, but not either one alone. This amounts to the second shevuah partially overlapping his first, by prohibiting already forbidden figs, and is thus parallel to the case of nezirus, in which the second nezirus overlaps twenty-nine days that were already forbidden by the first nezirus. The Gemara brings Rabbah who disagrees and holds that the second shevuah not to eat figs and grapes would take effect, since it is able to take effect regarding the grapes.
