1) THE PROHIBITION OF "AMIRAH L'NOCHRI"
QUESTION: The Mishnah (14b) states that selling a Behemah Gasah (a large domesticated animal, such as a cow) to a Nochri is prohibited. The Gemara explores the reason for this prohibition and proposes that it is due to the fear that the Nochri will make the animal work on Shabbos. The Gemara responds that this is not a valid reason to prohibit selling the animal to a Nochri, because once the Nochri has bought it, it no longer belongs to a Jew and it is permitted to work on Shabbos. RASHI (DH Keivan) explains that there is no prohibition of "Lifnei Iver" involved with selling an animal to a Nochri who will make the animal work on Shabbos, because the Nochri has no Mitzvah to observe Shabbos.
Rashi asks, however, that if a Nochri has no Mitzvah to observe Shabbos, then why is a Jew prohibited from telling a Nochri to do a Melachah for him on Shabbos? Rashi explains that it is prohibited because of the verse, "If you honor it (Shabbos) by not engaging in your own affairs, nor pursuing your own business, nor speaking of vain matters (v'Daber Davar)..." (Yeshayah 58:13). The Gemara in Shabbos (153b) teaches that the words "v'Daber Davar" refer to telling a Nochri to do Melachah on Shabbos.
The TESHUVOS PNEI YEHOSHUA (YD 2) quotes HA'GA'ON RABEINU REBBI HESHEL who asks that the Gemara in Bava Metzia (90a) seems to contradict the words of Rashi. The Gemara there inquires whether a Jew may tell a Nochri to muzzle the Jew's animal and use it to thresh the grain. The Jew himself is prohibited from muzzling his animal while it threshes because of the prohibition of "Lo Sachsom" (Devarim 25:4). The Gemara there is asking whether the prohibition against telling a Nochri to do an act which the Jew himself is prohibited from doing applies only to Shabbos, the laws of which are very severe (desecration of Shabbos is punishable with Sekilah), or whether it also applies to other prohibitions. The Gemara answers that a Jew is prohibited from telling a Nochri to do any act which the Jew himself is prohibited from doing, because the Nochri acts as the Shali'ach of the Jew. (Although a Nochri generally cannot be appointed as a Shali'ach, he is considered to have the ability to become a Shali'ach if being a Shali'ach will result in a stringency, l'Chumra.)
The Gemara there implies that the source for the law that a Jew may not tell a Nochri to do a Melachah for him on Shabbos is not the verse in Yeshayah that discusses Shabbos, because if that were the source, then the prohibition should apply only to Shabbos and not to other Isurim. What, then, is the source for the prohibition of "Amirah l'Nochri"? Moreover, what is the meaning of the words of Rashi here?
ANSWERS:
(a) The BEIS MEIR (#5) and CHASAM SOFER (OC 84) answer that with regard to doing a Melachah on Shabbos, a Jew cannot be liable for a Melachah done through Shelichus at all. Only when the act itself is inherently a repulsive act before Hash-m is the Nochri's act on behalf of the Jew attributed to the Jew. The act of a Melachah on Shabbos, however, is not an inherently repulsive act. Melachah is forbidden on Shabbos in order for a Jew to rest on Shabbos from constructive labor ("l'Ma'an Yanu'ach"). For this reason, a Jew is permitted mid'Oraisa to place a pot of raw food on the flame before Shabbos in order that it cook on Shabbos. Hence, the reason why a Jew may not ask a Nochri to do Melachah on Shabbos cannot be that the Nochri acts as the Shali'ach of the Jew, because the Jew himself is resting from Melachah and is fulfilling the requirement of "l'Ma'an Yanu'ach," and thus the Jew has done no Aveirah. Therefore, it is necessary to have a special prohibition of "Amirah l'Nochri" on Shabbos which, according to Rashi, is derived from the verse in Yeshayah. (See Insights to Bava Metzia 71:2.)
(b) The KEHILOS YAKOV (Avodah Zarah #8) suggests that there indeed are two reasons for why a Jew may not tell a Nochri to work on Shabbos. One is the verse in Yeshayah of "v'Daber Davar," and the other is the reason that the Nochri is acting as the Shali'ach of the Jew to do a prohibited act. The Gemara in Bava Metzia is discussing the second reason, while Rashi here is discussing the first.
Why, though, is a special reason needed to prohibit "Amirah l'Nochri" on Shabbos, if the prohibition of "Amirah l'Nochri" applies to all Isurim?
The Kehilos Yakov answers that both reasons are necessary. Without the reason of Shelichus, one would have thought that the verse of "v'Daber Davar" prohibits such speech only on Shabbos itself; only on Shabbos itself is one prohibited to tell a Nochri to do a Melachah, but before Shabbos one is permitted to tell a Nochri to do a Melachah later on Shabbos. However, the Halachah (according to the majority of Poskim; see BEIS YOSEF OC 307), prohibits this form of "Amirah l'Nochri" as well. The prohibition against telling a Nochri, before Shabbos, to do a Melachah on Shabbos must be due to the reason of Shelichus. On the other hand, without the verse in of "v'Daber Davar," one would have thought that the reason of Shelichus prohibits telling the Nochri to do one's work for him on Shabbos, but he is permitted to tell the Nochri on Shabbos to do work for him after Shabbos. The verse of "v'Daber Davar" teaches that this type of speech is forbidden on Shabbos altogether, even if the Melachah itself will not be done until after Shabbos.
(c) The Kehilos Yakov suggests another reason for why the verse of "v'Daber Davar" is necessary. The TOSFOS RID, SHACH (CM 292) and others discuss the concept that a person cannot be a Shali'ach to transgress a sin for someone else such that the sin will be attributed to the other person; if such a Shali'ach transgresses a sin, the sin is attributed to him. Although it is considered the Shali'ach's sin, nevertheless the sender still bears partial guilt; he is considered to have done part of the sin.
Accordingly, without the verse in Yeshayah, one would not have known that the concept of Shelichus prohibits a Jew from telling a Nochri to do a Melachah on Shabbos. This is because a Halachah in the laws of Shabbos states that two people who perform a forbidden Melachah together ("Shenayim she'Asu") are not guilty of transgressing the Torah's prohibition; the Torah prohibits only a person from doing a Melachah himself. Doing the Melachah with another person is prohibited only mid'Rabanan. This means that, according to these opinions, telling a Nochri to do a Melachah on Shabbos would be only a "Shevus d'Shevus," a rabbinical-level transgression of a rabbinical decree (that is, telling the Nochri to do Melachah is prohibited only mid'Rabanan, and the Melachah that one is telling him to do is only an Isur d'Rabanan, since it is considered as though two people are doing the Melachah together). The verse is needed, therefore, to teach that telling a Nochri to do Melachah on Shabbos is categorized as only one act of "Shevus" and is forbidden. (Y. MONTROSE)

15b----------------------------------------15b

2) SELLING AN ANIMAL TO A JEW WHO IS SUSPECTED OF SELLING ANIMALS TO NOCHRIM
QUESTION: The Gemara relates that Rabah sold his donkey to a Jew who was suspected of selling donkeys to Nochrim. When questioned about his conduct, he explained that since he sold it to a Jew and not to a Nochri, it was permitted. The Gemara later, however, concludes that one is forbidden to sell an animal to a Jew when that Jew will sell the animal to a Nochri.
OPINIONS: The Mishnah (13b) states that one is forbidden to sell Levonah (frankincense) to an idol-worshipper, since it is likely that he will use the Levonah to serve his idol. The Gemara earlier (14a) quotes a Tosefta which teaches that although it is generally forbidden to sell Levonah (frankincense) to an idol-worshipper, one is permitted to sell a large quantity, a "bundle" (Chavilah), of Levonah to an idol-worshipper. RASHI explains that since he is buying a large bundle, he probably wants it for commercial purposes and not for idol-worship. The Gemara asks that perhaps the idol-worshipper who is buying the bundle of Levonah will go and sell some of it to others who will use it for Avodah Zarah, and thus a Jew should not be permitted to sell to an idol-worshipper even a large quantity. Abaye answers that the Torah forbids one from causing another person to sin -- "v'Lifnei Iver Lo Siten Michshol" -- "Do not place a stumbling block before the blind" (Vayikra 19:14), but it does not forbid one from causing another person to cause another person to sin ("Lifnei d'Lifnei").
TOSFOS (DH l'Oved) asks that according to the Gemara earlier, the Gemara here should permit a Jew to sell his animal to another Jew, even when the other Jew is suspected of selling animals to Nochrim. Since selling the animal to that Jew constitutes only "Lifnei d'Lifnei," it should be permitted.
ANSWERS:
(a) TOSFOS quotes RABEINU ELCHANAN who answers that when Abaye says that the Torah does not prohibited one from doing an act of "Lifnei d'Lifnei," he means that the Torah does not prohibit one from causing a Nochri to cause someone else to do an Aveirah. Since a Nochri is not bound by the prohibition of "Lifnei Iver" and he is not prohibited from selling to another Nochri an object that the buyer will use for Avodah Zarah, a Jew is not prohibited from doing an act of "Lifnei d'Lifnei." The Gemara here, however, discusses selling an object to a Jew who might sin by selling the object to a Nochri. A Jew is commanded not to do any act which will cause another Jew to do any sin. Since the second Jew might sin (by selling the animal to a idol-worshipper and transgressing the prohibition of "Lifnei Iver") as a result of the first Jew's sale, the first Jew is not allowed to sell the animal to the suspected Jew. This also seems to be the way the MINCHAS CHINUCH (#232) understands the words of Tosfos.
Accordingly, Tosfos maintains that the case of the Gemara here is not a case of "Lifnei d'Lifnei," but rather a case in which there is only one "Lifnei." By selling the animal to the suspected Jew, the first Jew causes the second Jew to do an Isur himself (the Isur of selling the animal to a Nochri).
(b) Tosfos answers further that the first Jew transgresses "Lifnei Iver" (and not "Lifnei d'Lifnei") by selling the animal to the second Jew, because the second Jew is going to sin by lending or renting the animal to a Nochri (which is prohibited because of "Shevisas Behemto").
It is not clear what the difference is between the two answers of Tosfos. Both answers seem to say that the first Jew may not sell the animal to the suspected Jew because there is only one "Lifnei" involved, since it is the second Jew himself who will be sinning. In what way do these two answers differ? (See CHAVOS YA'IR #185, and MINCHAS YITZCHAK 3:79; see also RITVA to 14a, DH Tana. See also RAN, and CHIDUSHEI ANSHEI SHEM and SEDER YAKOV's understanding of the Ran.)
The KEHILOS YAKOV (#4) therefore understands Tosfos in an entirely different way. He explains that Tosfos is in doubt about whether or not the prohibition of "Lifnei Iver" applies to an Isur d'Rabanan, such as the Isur against selling an animal to a Nochri. The Kehilos Yakov explains that Tosfos initially assumes that when the first Jew sells the animal to the Jew who is suspected of selling it to a Nochri, it is considered as though the first Jew himself has transgressed the prohibition of selling the animal to a Nochri. Based on this understanding, Tosfos asks that the Gemara earlier -- which says that there is no prohibition of "Lifnei d'Lifnei" -- implies that the action done by the buyer (selling the animal to a Nochri who will use it for Avodah Zarah) is not considered as though it was done by the first seller, the Jew! Why, then, does the Gemara here say that the first Jew is not allowed to sell the animal to the second Jew? This is the question of Tosfos.
Tosfos answers that the Gemara's reason for prohibiting the first Jew from selling the animal to the suspected Jew is not as Tosfos initially assumes. It is not because the action eventually done by the second Jew is attributed to the first Jew, because the concept of "Lifnei d'Lifnei" teaches that the first Jew's act certainly should be permitted. The problem is that the suspected Jew will eventually transgress an Isur d'Rabanan because of the first Jew who sold him the animal. Tosfos concludes that the prohibition of "Lifnei Iver" means that every Jew is commanded to ensure that he causes no other Jew to sin in any way, and, therefore, "Lifnei Iver" applies even when the Isur that the second Jew might do is only an Isur d'Rabanan.
The Kehilos Yakov points out that according to this explanation, the text in Tosfos should be altered slightly so that it reads, "she'Lo Yavo Yisrael li'Yedei Shum Takalah" ("so that a Jew should not come to do any transgression") instead of "she'Lo Yavo Shum Yisrael li'Yedei Takalah" ("so that no Jew should come to do a transgression"). Such a text would emphasize that a Jew must be careful not to cause another Jew to transgress even an Isur d'Rabanan. (This is similar to the words of Tosfos later (22a) who cites this Gemara as proof that "Lifnei Iver" applies to an Isur d'Rabanan.)
The Kehilos Yakov explains that the second answer of Tosfos argues with the first. The second answer suggests that perhaps "Lifnei Iver" does not apply to an Isur d'Rabanan. The reason why the first Jew is prohibited from selling the animal to the second Jew is that the second Jew might also transgress an Isur d'Oraisa of "Shevisas Behemto" by lending or renting the animal to a Nochri, and thus the Isur of "Lifnei Iver" applies to the first Jew. (Y. MONTROSE)

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