OPINIONS: The Mishnah (2a) teaches that a Jew may not conduct a transaction with a Nochri three days before his holiday of Avodah Zarah. The Gemara asks whether such a transaction is forbidden because of "Harvachah" (causing the Nochri to profit and, as a result, give thanks to his god) or because of "Lifnei Iver Lo Siten Michshol" (causing the Nochri to sin).

What is the difference between the reason of "Harvachah" and the reason of "Lifnei Iver"?

The Gemara explains that the difference exists in a case of "Is Lei," in which the Nochri already has another animal to slaughter as a sacrifice for his Avodah Zarah. If the reason for the prohibition is "Harvachah," then dealing with the Nochri still should be forbidden, since he still will give thanks to his god. If the reason is "Lifnei Iver," then the Jew should be permitted to sell him the animal, since he has the ability to sin even before the transaction. The Gemara compares this case to one who helps a Nazir take a cup of wine when the Nazir is on the same side of the river as the wine. The one who helps the Nazir is not enabling him to transgress, since he already has the ability to do the sin without the other person's help. The prohibition of "Lifnei Iver" applies only when the Nazir cannot easily reach the wine by himself, such as when he is on the other side of the river. One who gives him the wine in such a case transgresses "Lifnei Iver."

The Gemara implies that the prohibition of "Lifnei Iver" is defined as enabling a person to commit a sin which he otherwise would not have been able to commit. Is this indeed the meaning of "Lifnei Iver"?

(a) This is the way TOSFOS in Chagigah (13a, DH Ein) understands the prohibition of "Lifnei Iver." Tosfos there asks why the Gemara needs to cite a verse to teach that one may not teach Torah to a Nochri. Since a Nochri is forbidden from learning any part of Torah other than what he needs to know in order to fulfill the seven Mitzvos of Bnei Noach, the prohibition of "Lifnei Iver" should suffice to prohibit a Jew from teaching Torah to a Nochri. Tosfos answers that if another Nochri is willing to teach him, then the prohibition of "Lifnei Iver" does not apply and, if not for the special verse, the Jew would be permitted to teach him.

This is also the view of the MORDECHAI here (6b). The Mordechai writes in the name of the BEHAG that a Jew may lend money to Nochrim nowadays, and "even though they give some of that money to the caretaker of their shrine on their holiday, they do not give so much money to the caretaker that they could not borrow that amount of money from a different source."

This explanation of the prohibition of "Lifnei Iver" is also endorsed by the ME'IRI, who writes that a Jew may sell to Nochrim forbidden food items since they can buy the same items elsewhere.

(b) The BI'UR HA'GRA (YD 151:8) disagrees with this definition of "Lifnei Iver." He cites the Gemara in Nedarim (62b) which relates that Rav Ashi sold a forest to the servants of a fire-god, who worshipped their god by burning wood to it. When Ravina asked him why such a sale does not constitute "Lifnei Iver," Rav Ashi replied that "most firewood is used for heating." The Bi'ur ha'Gra asks that according to the Mordechai, Ravina's question does not make sense. Why would Rav Ashi transgress "Lifnei Iver" by selling wood to the servants of a fire-god? Since they could have bought wood from someone else, the prohibition of "Lifnei Iver" did not apply! It must be that the prohibition of "Lifnei Iver" applies even when the person can find another way to sin. What, then, does the Gemara mean when it answers that the difference between the reason of "Harvachah" and the reason of "Lifnei Iver" is a case of "Is Lei"?

The Bi'ur ha'Gra explains that "Is Lei" means that the Nochri actually has in his possession the item with which to do the sin. However, if the potential sinner does not own the item, then even if it can be found in stores and can be acquired from others, the first person to sell it to him transgresses "Lifnei Iver."

This is also the view of the EMUNAS SHMUEL (#14, quoted by the PISCHEI TESHUVAH, YD 151:2). The Emunas Shmuel points out that the Gemara says merely "Is Lei" -- "he has the object," and not that he has the ability to acquire it from another source. Moreover, if the Gemara means that he does not have the object but that he has the ability to acquire it from another source, then the prohibition against selling an animal to a Nochri three days before his holiday, according to the reason of "Lifnei Iver," would apply only in a very rare case in which no other animals are available to buy.

OPINIONS: The Gemara teaches that one transgresses "Lifnei Iver" when he helps a Nazir obtain a cup of wine that is not on the same side of the river as the Nazir, since he enables the Nazir to transgress his prohibition against drinking wine. If the wine and Nazir are on the same side of the river, one does not transgress "Lifnei Iver," since the Nazir already has the ability to sin, even though he helps him ("Mesayei'a") obtain the forbidden wine. Does this mean that one is permitted to give the Nazir wine in such a situation?

(a) The RAN (1b of the pages of the Rif) writes that when the wine is on the same side of the river as the Nazir, one is prohibited mid'Rabanan from giving it to the Nazir, since "he is obligated to stop him from sinning, and how can he help him sin!" RASHI (55b, DH v'Yisrael) makes a similar statement, although with a slightly different logic. Rashi writes that "we are forbidden to help a person who is sinning; rather, we stay away from him so that he should not be accustomed to sinning." While the Ran's logic is that one is obligated to stop another Jew from sinning, Rashi seems to understand that one must not create an atmosphere where a person feels comfortable with his sinful ways. This prohibition is also mentioned by TOSFOS and the ROSH in Shabbos (3a).

(b) However, TOSFOS here (DH Minayin) apparently maintains that such an act is prohibited, and that there is no such prohibition as "Mesayei'a." Tosfos infers from the Gemara's conclusion that a person may not extend ("Moshit") a forbidden item (such as Neveilah) to a person who wants to sin with it, but he may extend such an item to a person who does not want to sin with it (but wants to throw it out, for example). Tosfos adds that this applies even to extending a forbidden item to a Yisrael Mumar l'Avodah Zarah (an apostate Jew who worships Avodah Zarah), since he still has the status of a Jew. Tosfos concludes, "And this refers to a case in which he cannot obtain it himself if the other person does not extend it to him, as the Gemara here concludes that the case refers to two sides of the river."

Tosfos makes no mention of "Mesayei'a" at all, implying that when the sinner is able to obtain the object in some other way, there is no prohibition against giving it to him. This also seems to be the position of Tosfos in Chagigah (13a, DH Ein).

Tosfos there asks why the Gemara needs to cite a verse to teach that one may not teach Torah to a Nochri. Since a Nochri is forbidden from learning any part of Torah other than what he needs to know in order to fulfill the seven Mitzvos of Bnei Noach, the prohibition of "Lifnei Iver" should suffice to prohibit a Jew from teaching Torah to a Nochri. Tosfos answers that if another Nochri is willing to teach him, then the prohibition of "Lifnei Iver" does not apply and, if not for the special verse, the Jew would be permitted to teach him.

Similarly, the Mordechai here writes in the name of the BEHAG that a Jew may lend money to Nochrim nowadays, and "even though they give some of that money to the caretaker of their shrine on their holiday, they do not give so much money to the caretaker that they could not borrow that amount of money from a different source." The Mordechai implies that one is permitted, even mid'Rabanan, to help a person who anyway has access to the forbidden item. Do these Rishonim indeed maintain that there is no prohibition of "Mesayei'a"?

1. The REMA (YD 151:2) seems to learn this way. He writes that "there are some who say" that a Jew may not sell Avodah Zarah items to Nochrim if they do not have other similar items or are unable to buy them elsewhere. If they have such items or are able to buy them elsewhere, then the Jew may sell such items to the Nochrim. The Rema continues: "Some are stringent, and the custom is to be lenient like the first opinion, but a Ba'al Nefesh should be stringent for himself." The DARCHEI MOSHE HA'ARUCH (ibid.) explains that Tosfos here and other Rishonim maintain that there is no prohibition of "Mesayei'a," even to help a Jew sin, as long as it does not constitute the Torah prohibition of "Lifnei Iver." However, some say that the Rema's words, "the custom is to be lenient," refer only to selling Avodah Zarah items, and the leniency is based on the Rema's own opinion that Nochrim today are not really idolaters. (See SHACH YD 151:7, who writes that this is implied in the Darchei Moshe.)

2. The SHACH (YD 151:6) disagrees with the Rema and maintains that the Rishonim do not argue with each other at all. Rather, the Rishonim agree that there is an Isur d'Rabanan of "Mesayei'a" which prohibits helping another Jew sin, and there is no such prohibition against helping a Nochri sin. The sources which are lenient refer specifically to helping a Nochri sin, while the sources which are stringent refer specifically to helping a Jew sin. Tosfos in Avodah Zarah (DH Minayin) adds merely that a Mumar l'Avodah Zarah is like a Jew with regard to the prohibition of "Lifnei Iver," implying that he is like a Nochri with regard to the prohibition of "Mesayei'a." The Shach asserts that everyone agrees with this.

The Shach proves his view from a contradiction in the words of the ROSH and in the words of RABEINU YERUCHAM. According to the Rema's understanding, the Rosh in Avodah Zarah says that there is no Isur of "Mesayei'a." However, in Shabbos (3a) the Rosh clearly says that there is such an Isur. Similarly, Rabeinu Yerucham (Nesiv 17:6) rules like Tosfos in Avodah Zarah, but elsewhere (Nesiv 12:3) he rules like the Rosh in Shabbos. The Shach concludes that the only way to reconcile these contradictions is to say that there is a difference between a Jew and a Nochri; when the Rosh and Rabeinu Yerucham rule that "Mesayei'a" is forbidden, they refer to helping a Jew sin, and when they rule that it is not forbidden, they refer to helping a Nochri sin.

However, there seems to be an explicit opinion that maintains that the Isur of "Mesayei'a" applies even to helping a Nochri sin. RASHI (55a, DH Dorchin) discusses the question of helping a Nochri be Metamei Chulin in Eretz Yisrael, an act which is forbidden for a Jew to do. Rashi writes that one is permitted to help a Nochri do such an act, since the Nochri "is not commanded on this." This implies that for a law which the Nochri is commanded to observe, one would not be permitted to help him transgress because of the Isur of "Mesayei'a." (See previous insight with regard to the opinion of the BI'UR HA'GRA and the EMUNAS SHMUEL.) (Y. MONTROSE)