1) REDEEMING A TORAH SCHOLAR FROM CAPTIVES FOR AN EXORBITANT SUM
OPINIONS: The Mishnah teaches that because of "Tikun ha'Olam" we may not redeem captives for more than their actual monetary value. The Gemara asks what the Mishnah means by "Tikun ha'Olam." Does "Tikum ha'Olam" refer to preventing the impoverishment of the community, "Duchka d'Tzibura," which would occur if the community would be required to free captives for whatever sum the captors demand, or does the term refer to deterring criminals from increasing their efforts to kidnap additional people?
RASHI (DH O Dilma) writes that the difference between the two explanations exists in a case in which the captive has a wealthy relative who is willing to shoulder the exorbitant ransom himself. According to the first reason, he should be allowed to pay the ransom because his capitulation to the captors' demand will not impoverish the community. According to the second reason, he should not be allowed to pay the ransom because his capitulation will encourage the captors to kidnap more people. The Gemara here does not conclude which explanation is the correct one for the Mishnah's reason of "Tikun ha'Olam."
The Gemara later (58a), however, apparently does rule in accordance with one of the two explanations. The Beraisa there relates that Rebbi Yehoshua ben Chananya once traveled to a large city in Rome. He was told that there was a handsome, young Jew sitting in prison. Rebbi Yehoshua stood at the entrance of the prison and recited the verse, "Who gave Yakov over for spoils and Yisrael to plunderers?" (Yeshayah 42:24). The boy in prison answered with the end of the verse, "Is it not Hash-m to Whom we have sinned?" Rebbi Yehoshua declared that he was certain that the boy was destined to become a "Moreh Hora'ah" for the Jewish people. Rebbi Yehoshua swore that he would not leave until he redeemed the boy from prison, even if his captors would demand a large ransom. He indeed redeemed the boy for a large ransom, and as he predicted the boy became a leader of the Jewish people -- Rebbi Yishmael ben Elisha.
Why was Rebbi Yehoshua permitted to redeem the boy for an exorbitant sum of money, if the Mishnah here states that one may not redeem a captive for more than his market value? It must be that Rebbi Yehoshua maintained that the Mishnah's reasoning is "Duchka d'Tzibura."
Is this indeed the conclusion of the Gemara?
(a) TOSFOS (DH d'Lo) and the RITVA challenge the second explanation of the Gemara here from the incident involving Rebbi Yehoshua ben Chananya. Tosfos answers that "the boy was exceptionally wise." How does this answer the question, why did Rebbi Yehoshua permit himself to redeem the captive for an exorbitant sum?
The RAMBAN explains that when a Talmid Chacham is taken captive, he must be redeemed for whatever sum of money the captors demand. This is because a Talmid Chacham is irreplaceable, as the Gemara in Horayos (13a) teaches. The Gemara there rules that in a case in which a Talmid Chacham and a Jewish king have been taken captive, the Talmid Chacham is redeemed first because he is irreplaceable, while any Jew can become king. Similarly, the community can replace its wealth, but it cannot so easily replace its Talmidei Chachamim. Accordingly, the reason of "Duchka d'Tzibura" does not apply when the captive is a Talmid Chacham. When Rebbi Yehoshua realized that the boy was a Talmid Chacham, he was willing to pay more than his market value to free him.
(b) Alternatively, Tosfos answers that the incident involving Rebbi Yehoshua ben Chananya occurred at the time of the destruction of the Beis ha'Mikdash. The RAMBAN explains that at the time of the Churban, the necessity to prevent criminals from increasing their efforts to take captives did not apply; at the time of the Churban, all Jews were in imminent danger of becoming captives.
(c) TOSFOS later (58a, DH Kol) explains that the Mishnah's ruling that one must not overpay to redeem captives applies only when the captives are not in mortal danger. Tosfos proves this from the Gemara (47a) which says that although one normally should not redeem a Jew who sold himself as a slave to Nochrim, if the Jew's life is in danger one may redeem him. Tosfos understands from the Gemara there that different rules apply to captives who are in mortal danger.
The RAMBAN rejects this answer. He argues that the Mishnah here certainly refers to captives in mortal danger, as all captives are constantly faced with a threat of losing their lives. (For further discussion on the subject, see PISCHEI TESHUVAH, YD 252:4). (D. Bloom)

45b----------------------------------------45b

2) THE DIFFERENCE BETWEEN A MINOR'S OBLIGATION TO OBSERVE "MITZVOS LO TA'ASEH" AND HIS OBLIGATION TO OBSERVE "MITZVOS ASEH"
QUESTION: Rav Hamnuna teaches that a Sefer Torah, Tefilin, and Mezuzos written by a heretic, informer, Nochri, slave, woman, or minor are unfit for use. This is derived from the verses in Devarim (11:18-20) which state that one must bind the Tefilin to his arm and he must write Mezuzos. The proximity of these commandments teach that one who observes the Mitzvah of Tefilin is eligible to write Mezuzos, while one who does not observe the Mitzvah of Tefilin (either because he is a heretic who rejects the Mitzvah or because he is not commanded by the Torah to wear Tefilin) may not write Mezuzos (and, similarly, he may not write a Sefer Torah or Tefilin).
The Gemara implies that a minor may not write a Sefer Torah, Tefilin, and Mezuzos because he is exempt from the Mitzvah of Tefilin.
However, this apparently contradicts the Mishnah in Chulin (2a) which states that if a minor slaughters an animal when others are present to see that he performs the Shechitah properly, the Shechitah is valid. The Mishnah there implies that a minor is commanded to fulfill the Mitzvah of Shechitah. Furthermore, the Mishnah in Chulin (12a) states that when a Nochri slaughters an animal his Shechitah is invalid and the animal has the status of a Neveilah. TOSFOS (Chulin 3b, DH Kasavar) explains that this is derived from the verse, "v'Zavachta... v'Achalta" -- "and you shall slaughter... and you shall eat" (Devarim 12:21), which teaches that one may eat meat only when the animal was slaughtered by a "Bar Zevichah" -- "one who is commanded to fulfill the Mitzvah of slaughtering." Since a Nochri is not a "Bar Zevichah," one may not eat the meat from an animal he slaughtered. Since the Gemara does not cite this verse as a problem with regard to an animal slaughtered by a minor, it apparently maintains that a minor is considered a "Bar Zevichah," commanded to fulfill the Mitzvah of Shechitah. How is it possible that a minor is commanded by the Torah to fulfill the Mitzvah of Shechitah but not the Mitzvah of Tefilin?
ANSWER: The KEHILOS YAKOV in Yevamos (31:7, DH v'Yisyashev) answers that there is a difference between positive commandments (Mitzvos Aseh) and negative commandments (Mitzvos Lo Ta'aseh). A minor is considered obligated to observe Mitzvos Lo Ta'aseh even though he is not liable for failure to observe them. This is evident from the Halachah that an adult is not permitted to feed a minor non-kosher food to minors (Yevamos 114a). Indeed, the SHACH (YD 1:27) states that this Halachah proves that a minor is commanded in Shechitah. Accordingly, a minor is considered a "Bar Zevichah" since he may eat only slaughtered meat. However, a minor has no obligation to observe Mitzvos Aseh (and, according to many opinions, an adult may even give him an object that will cause him to transgress a Mitzvas Aseh; see MAGEN AVRAHAM OC 269:1). Since a minor is not obligated to observe Mitzvos Aseh, he has no obligation to wear Tefilin. Therefore, he may not write a Sefer Torah, Tefilin, or Mezuzos.
The Kehilos Yakov cites further proof from the Gemara in Berachos (20b) that a minor is not obligated to observe Mitzvos Aseh. The Gemara there teaches that a minor may not recite Birkas ha'Mazon to exempt his father from his obligation, because the minor is obligated only mid'Rabanan to say Birkas ha'Mazon while the father is obligated mid'Oraisa. (See RASHI to Berachos 48a, DH Ad, who writes that the minor himself is not even obligated mid'Rabanan; rather, the father is obligated mid'Rabanan to teach his child to perform the Mitzvos.)
Accordingly, not only is a minor not subject to punishment for failure to observe a Mitzvas Aseh, he is not commanded at all to observe a Mitzvas Aseh.
The Kehilos Yakov cites the TERUMAS HA'DESHEN (Pesakim u'Kesavim #62) who apparently disagrees with the words of the Shach (who states that minors are obligated in the Mitzvah of Shechitah). The Terumas ha'Deshen maintains that not only does a minor receive no punishment for transgressing a Lo Ta'aseh, he is also not commanded at all by the Torah to observe those commandments. However, the Kehilos Yakov asserts that even the Terumas ha'Deshen may agree that a minor is a "Bar Zevichah." The Gemara in Yevamos (114a) clearly states that the Torah prohibits an adult from feeding non-kosher food to a minor. Even if the minor himself is not commanded to observe the Mitzvah of Shechitah, he still has an interest in an animal's Shechitah because the Torah forbids adults from feeding him meat from an animal that was not slaughtered. This gives him the status of a "Bar Zevichah."
(It should be noted that the Kehilos Yakov in Sukah (2:2) seemingly contradicts the approach he writes in Yevamos. In Sukah, he writes that a minor who recites Birkas ha'Mazon certainly fulfills the Mitzvah d'Oraisa of Birkas ha'Mazon. He explains that a minor is commanded to observe all of the Mitzvos, like every other Jew. He merely is exempt from performing the Mitzvos because he lacks the intellectual capacity to do so. This is also the view of RAV MOSHE FEINSTEIN (Igros Moshe YD 1:6), who asserts that when a minor fulfills a Mitzvah he even receives reward like one who is "Metzuveh v'Oseh" -- one who is commanded [to do the Mitzvah] and does it; the minor indeed is commanded, but he merely has an excuse (lack of intellectual maturity) which exempts him from fulfilling the Mitzvah. This approach is in opposition to the view of the TAZ in DIVREI DAVID to Devarim (31:12), who clearly states that a minor certainly is not "Metzuveh v'Oseh," as he is not punished for failure to fulfill a commandment. (See also YOSHEV OHALIM to Devarim ibid.) (D. Bloom, Y. Montrose)