1) A SHEVU'AH TO FULFILL A MITZVAH
OPINIONS: The Gemara says that a person may make a Shevu'ah to fulfill a Mitzvah for the sake of "l'Zaruzei Nafshei," to motivate himself. Is such a Shevu'ah binding?
(a) The RAN implies that the Shevu'ah indeed is binding, and if the person does not perform the Mitzvah he will receive Malkus for transgressing his Shevu'ah.
The Ran does not distinguish between a Shevu'ah to fulfill a Mitzvas Aseh (a positive Mitzvah) and a Shevu'ah to observe a Lo Ta'aseh (a negative Mitzvah). Even if he makes a Shevu'ah not to transgress a Mitzvah of "Shev v'Al Ta'aseh," the Shevu'ah takes effect and he will receive Malkus if he violates it by transgressing the Aveirah. However, he will not be obligated to bring a Korban if he violates the Shevu'ah, because such a Shevu'ah does not fulfill the condition of "l'Hara o l'Heitiv" (Vayikra 5:4).
(b) The BA'AL HA'ME'OR in Shevu'os (27a) writes that his Shevu'ah takes effect to obligate him to fulfill a Mitzvas Aseh. If he transgresses his Shevu'ah, he will be Chayav Malkus and a Korban. However, a Shevu'ah not to transgress a "Shev v'Al Ta'aseh" does not take effect at all, and if he transgresses he is not punished for violating his Shevu'ah (because his Shevu'ah does not fulfill the condition of "l'Hara O l'Heitiv" (Vayikra 5:4)).
(c) The RAMBAN (in MILCHAMOS in Shevu'os, and in his commentary on the Torah, as cited by the GILYON HA'SHAS) writes that a Shevu'ah cannot obligate a person to fulfill a Mitzvas Aseh or to refrain from transgressing a Lo Ta'aseh. When the Gemara says that it takes effect, it means merely that he is not considered to have spoken the Name of Hash-m in vain when he made his "Shevu'ah." (The ROSH adds that the Gemara also may means that there is no fear that he will become accustomed to pronouncing Shevu'os, and thus he is permitted to make such a Shevu'ah to motivate himself to fulfill a Mitzvah.)

8b----------------------------------------8b

2) A HUSBAND WHO ACTS AS A "SHALI'ACH" FOR THE ANNULMENT OF HIS WIFE'S NEDER
QUESTION: The Gemara discusses whether a man may serve as a Shali'ach of his wife in order to ask Beis Din to annul his wife's Neder.
Why does the Gemara ask whether a husband may serve as a Shali'ach to annul his wife's Neder? It should ask whether Beis Din may annul anyone's Neder in the absence of the Noder, the person who made the Neder ("she'Lo b'Fanav")!
ANSWERS:
(a) The RAMBAM (cited by the Ran) explains that under ordinary circumstances, Beis Din may not annul a Neder in the absence of the Noder. A special dispensation is given in the case of a wife's Neder, which Beis Din may annul when the husband is present, because of the principle of "Ishto k'Gufo."
(b) The Ran cites TOSFOS who answers that Beis Din normally may annul a Neder in the absence of the Noder. The Gemara here asks specifically about a person's wife: perhaps Beis Din may not annul her Neder when the request is brought before them by her husband as her Shali'ach, because of the concern that he might misrepresent his wife and alter what she said in order to ensure that the Beis Din will annul the Neder which causes him trouble and aggravation. This explanation is consistent with the Gemara's conclusion, that if he needs to gather people together in order to annul her Neder, there is greater reason to be concerned that he will change what his wife said in order to have the Neder annulled, since he troubled himself even more for her.
(c) The ROSH (1:7) explains that Beis Din normally may annul a Neder in the absence of the Noder. However, when a woman sends her husband to request annulment for her Neder on her behalf, there is a concern that she might have sent him only on condition that he not publicize her Neder, because she will be embarrassed if it is publicized. This is why the Gemara concludes that only if the husband finds three people already assembled is he allowed to request annulment of her Neder on her behalf. If he does not find three people assembled in one place and must collect people in order to make a Beis Din to annul the Neder, he may not serve as his wife's Shali'ach, because had his wife known that he would spread the word of her Neder she would not have sent him to annul it, and she would not have regretted that she made the Neder. (According to the Rosh, it is not clear why this Halachah applies only to a woman who sends her husband to annul her Neder. It should apply to any person who sends a Shali'ach to Beis Din to annul his Neder! Perhaps a woman is more sensitive to having her Neder publicized. When the Gemara says that the woman sends her husband, it includes any Shali'ach whom she might send.)
HALACHAH:
(a) With regard to annulment of a Neder in the absence of the Noder, the Halachah follows the view of the Rambam that Beis Din may not annul a Neder in the absence of the Noder (SHULCHAN ARUCH YD 228:16). The question of the Gemara applies only in the case of a husband who acts as a Shali'ach for his wife (in which case the Neder may be annulled because of "Ishto k'Gufo").
When the Noder is present in Beis Din but the interaction is conducted through a "Turgeman," a translator, Beis Din may annul the Neder (Shulchan Aruch ibid.).
(b) In the case of a Shali'ach of the wife, the Shali'ach may have her Neder annulled only when he finds three people ready to serve as a Beis Din to annul her Neder (SHULCHAN ARUCH YD 234:56). If he must gather people together to form a Beis Din, he may not annul her Neder, since she would be embarrassed if she knew that he was gathering people together and publicizing her Neder (as the Rosh says).
The SHACH (234:71) adds that since the reason why the Shali'ach may not gather people together is because she might not want her Neder publicized (and she retracts her regret if she knows that the Shali'ach is publicizing her Neder), if she explicitly gives him permission to gather three people together to annul her Neder, then he may do so.
(c) The RASHBA (Teshuvos) rules that when a person sends his request for annulment and his reason for regret to Beis Din in writing (Kesav) and requests that Beis Din annul his Neder, his written request is more reliable than a Shali'ach and Beis Din may annul his Neder based on his Kesav.
The TAZ (228:20), however, argues that a written request is no better than a Shali'ach. His argument is based on the Gemara in Ta'anis (4a) which says that Yiftach did not have his Neder annulled because he felt it was below his dignity to appear before Pinchas, the head of the Beis Din, to request annulment for his Neder. The RIVASH infers from the Gemara there that Pinchas was unable to annul the Neder in the absence of Yiftach, "she'Lo b'Fanav." The Taz asserts that if a person may send to Beis Din a written request for the annulment of a Neder, Yiftach should have simply submitted a written request and Pinchas would have annulled the Neder based on Yiftach's request. It must be that a written request is not valid for Hataras Nedarim.
3) AGADAH: TZADIKIM AND THE SUN
QUESTION: Reish Lakish states that "in the World to Come, there will be no Gehinom. Rather, Hash-m will remove the sun from its sheath, and the righteous will be healed by it, while the wicked will be punished by it, as it says (Malachi 3:19), 'A sun will come which will burn like a furnace; all the wicked and all the evildoers will be like straw, and the sun will incinerate them.... But a sun of kindness will shine for those who fear Me, with healing in its rays.' Moreover, the righteous will derive pleasure from the sun, as it says (ibid.), '... and you will become sated, as fattened calves entering their pen to feed.'"
According to the verse in Malachi, the righteous will not need shelter from the burning sun on the Day of Judgment. On the contrary, the warmth of the sun on that day will benefit them, rather than harm them. This description, however, seems to contradict Reish Lakish's own description of the events that will take place in the future. The Midrash (Yalkut Shimoni, Emor #653) quotes Reish Lakish who says that in the World to Come, "at that time Hash-m will make a Sukah (a shelter of shade) for the righteous to protect them from the sun, as it says (Tehilim 27:5), 'He will conceal me in His Sukah on the day of evil; He will hide me in the seclusion of His tent.'" Reish Lakish implies that the sun will be harmful to the Tzadikim, and thus they will require shelter from it! How are these two statements of Reish Lakish to be reconciled? How can the righteous both benefit from the sun, and require shelter from its harmful rays?
ANSWER: To answer this question, several other questions need to be addressed. Why was the sun chosen to be the agent through which Hash-m will administer punishment for the wicked and reward for the righteous? What is meant by the sun's "sheath," and why is it normally encased in this sheath? What does the Sukah that Hash-m will construct for the righteous represent?
The Gemara in Sotah (10a) teaches that the word "Shemesh" ("protector"; Rashi) is used as an appellation for Hash-m, as it says, "Hash-m is a Shemesh and a shield" (Tehilim 84:12). The common usage of the word "Shemesh," however, is the word for "sun." Why should the sun be called by the same word that denotes its Creator?
The verse states, "The heavens proclaim the glory of Hash-m... He made a tent [in the heavens] for the sun. The sun appears like a groom who emerges from his bridal canopy; it rejoices like an athlete who runs his course. It emerges from one edge of the sky and goes around to the other; no one can escape its heat" (Tehilim 19:2-7). In what way do "the heavens proclaim the glory of Hash-m"? The verse explains that it is through the sun's great might that Hash-m's power is demonstrated. The sun's colossal nuclear furnace, which radiates more energy every second than mankind has consumed in history, is the source of all life on earth. Holding in tow the entire solar system through its gravitational pull, the sun's light, heat, and "wind" of ionized particles affect planets and other bodies billions of miles away. The sun, earth's only directly observable star, is the greatest public demonstration of the awesome might and glory of Hash-m.
In fact, it was this very display of power that brought ancient civilizations to worship the sun. In truth, however, the sun itself can do nothing to change its predetermined, natural course. It persistently "emerges from one edge of the sky and it goes around to the other." Instead of worshipping it, mankind must marvel at the great Power Who endows the sun with such tremendous might.
This is why the word "Shemesh," which is used to describe Hash-m, is also used as a name for the sun, Hash-m's great emissary in this world. An emissary is entitled to go by the name of his dispatcher.
In this world, however, the "sun" -- the demonstration of Hash-m's glory to man which the sun represents -- is "sheathed." It is still possible for man to make the mistake of thinking that the sun functions on its own, or that the sun acts according to natural principles which developed spontaneously and randomly. The "brilliance" of the sun is thus "covered" and concealed in this world.
In the World to Come, however, Hash-m will take the sun out of its "sheath." As the Gemara in Berachos (17a) says, "In the world to come there will be no eating or drinking; rather, the righteous will sit and delight in the radiance of Hash-m's presence." Experiencing closeness to Hash-m will replace physical pleasure for the righteous. They will be able to perceive Hash-m in a way that is not possible in this world. Hence, the sun will be "taken out of its sheath," as a reward for those who sought throughout their lives to know Hash-m and His ways better. Hash-m will reveal His glory to every righteous person in the World to Come in accordance with the amount of effort each one invested in knowing and understanding Hash-m during his life in this world.
The wicked, on the other hand, will endure disgrace at that time. It will become abundantly clear just how much they distanced themselves from the source of eternal life during their sojourn in this world. On the Day of Judgment, their disgrace will be revealed to all, and any existence that they merit will be granted to them only through the righteous men whom they despised during their lives. The revelation of Hash-m's presence in the World to Come will "burn" them due to the their distance from Him.
The reward of the righteous will be granted based on an evaluation of the degree of closeness with their Creator which they achieved during their lives. It therefore stands to reason that even among the righteous, every person's experience in the World to Come will be different. Some will be closer than others to Hash-m in certain aspects, while others will be closer in other ways. Accordingly, the righteous will both "derive pleasure from the sun (the revelation of the Divine Presence)" in the merit of their accomplishments, and "be burned by the sun" for their failings. Since they are righteous, however, and they at least worked towards "knowing Hash-m," He will make for them a Sukah to protect them from being scorched for their failings. Hence, Reish Lakish's two statements complement each other. The righteous will both be rewarded by the sun, and yet need protection from it.