1) HALACHAH: MELACHAH DONE ON SHABBOS BY A NOCHRI
OPINIONS: If a Nochri does Melachah on Shabbos for a Jew, may the Jew benefit from that Melachah? If he may benefit from it, when may he benefit from it?
(a) RASHI (in the Mishnah, DH Lo Yispod, and in the Gemara, DH Tanya) appears to maintain that if a Nochri does Melachah for a specific Jew, that Jew may never benefit from the Melachah.
Other Jews, however, may benefit from it after Shabbos, after the time has passed in which they would have been able to do the Melachah themselves ("bi'Chedei she'Ya'asu"). Similarly, if the Melachah was not done for any specific Jew, then anyone may benefit from it after Shabbos "bi'Chedei she'Ya'asu."
(b) The RAN and other Rishonim argue. They say that the results of a Melachah normally do not become forbidden forever, even if the Melachah was done for a specific Jew. Only when a Nochri does a Melachah openly, in public, for a Jew, may the Jew not benefit from it forever. If the Melachah is done in a normal manner (not in public), even the specific Jew for whom it was done may benefit from it after Shabbos "bi'Chedei she'Ya'asu" like everyone else.
(c) The RAN cites an opinion that maintains that a Jew may benefit from Melachah that was not done specifically for him immediately, even on Shabbos (provided that it is something that may be used on Shabbos).
HALACHAH: The SHULCHAN ARUCH (OC 325:14-15) rules like the RAN (b) that benefit from the Melachah is forbidden forever for the Jew for whom the Melachah was done, when it was done for him in public. If it was not done in public, then it is forbidden (for everyone) only until after Shabbos "bi'Chedei she'Ya'asu." The TUR adds that if the Jew asks the Nochri to do the Melachah for him, it is forbidden for that Jew forever. The MISHNAH BERURAH (325:74), however, is lenient in this regard and writes that it is only forbidden until after Shabbos "bi'Chedei she'Ya'asu."
If the Melachah that the Nochri did involved bringing an object from outside of the Techum (Shabbos boundary), then it is forbidden only for the person for whom it was brought, but everyone else may use it immediately, even on Shabbos.
2) HALACHAH: A DOUBT WHETHER A NOCHRI DID A MELACHAH FOR A JEW ON SHABBOS
OPINIONS: Rav and Shmuel dispute whether a Jew may derive benefit from a Melachah done by a Nochri when there is a doubt whether the Nochri did the Melachah on Shabbos or before Shabbos, and when there is a doubt whether he did it for other Nochrim or for Jews. The Gemara (according to the text of most Rishonim) adduces proof for Shmuel from a Beraisa. What is the Halachah?
The Rishonim rule in accordance with Shmuel. However, there are two ways to interpret Shmuel's opinion.
(a) RASHI says that Shmuel is more lenient than Rav and allows one to benefit from an act done by a Nochri on Shabbos even when there is a possibility that the act involved a Melachah.
(b) The RIF and RAMBAM understand Shmuel to be more stringent than Rav, since he uses the word "Chaishinan" ("we are concerned"), which is almost always used to describe a stringency. Shmuel maintains that we must know for certain that Melachah was not done in order to permit a Jew to benefit from the Nochri's act. The Gemara cites a Beraisa that proves the more stringent opinion (the proof is from the Tana Kama).
HALACHAH: The SHULCHAN ARUCH (OC 325:16) follows the stringent opinion and rules that one is permitted to benefit from an act done by a Nochri on Shabbos only when it is known for certain that he did not do a Melachah specifically for a Jew.
3) A SMALL BATH HEATED BY NOCHRIM
QUESTIONS: In the Beraisa, Rebbi Yehudah says that a Jew is permitted to bathe in the hot water of a small tub immediately after Shabbos, if there is a non-Jewish figure of authority in the town who has many servants who can heat up a tub of water for him. RASHI (DH b'Ambati, DH Rochetz) explains that one may bathe in a small tub because it can be assumed that the hot water inside of it was heated after Shabbos by one of the many servants of the figure of authority, and therefore a Jew may wash in it after Shabbos.
(a) In an earlier comment, Rashi (DH Tanya Kevasei d'Rav) explains that this Beraisa follows the opinion of Rav, who maintains that when there is a doubt whether the Melachah was done for a Jew or not, one is not permitted to benefit from it. According to Rashi, why does the Beraisa permit one to bathe in the tub even where there is a non-Jewish figure of authority? It is not certain that the tub was heated for him!
(b) Second, why does Rashi say that when there is a ruler, perhaps the bath was heated after Shabbos? What difference does it make when the bath was heated? Even if it was heated on Shabbos, since it was heated for a Nochri it is permissible for a Jew to bathe in it after Shabbos!
ANSWER: The Beraisa's ruling with regard to a small tub is a continuation of the case that it previously presented -- if a Nochri heated a bathhouse in a place where half the residents are Jews and half are Nochrim, a Jew may not benefit from that Melachah until after Shabbos "bi'Chedei she'Ya'asu" (see above, Insight #1), because it might have been heated for the Jews.
The Beraisa continues and says that where there is a non-Jewish figure of authority, there is a new point of uncertainty -- perhaps the bath was heated after Shabbos. Consequently, there are two doubts: perhaps it was heated after Shabbos, and even if it was heated on Shabbos, perhaps it was heated for the Nochri.
This answers both of our questions. Even Rav permits one to benefit from the Nochri's Melachah immediately after Shabbos in such a situation, since it is a Sfek Sfeika. (This is known as a "Sfek Sfeika she'Einah Mis'hapech.") Rashi emphasizes that the figure of authority is a Nochri in order to provide the second Safek. (M. KORNFELD)
(According to Rashi's second explanation, the Beraisa expresses the opinion of Shmuel: when there is a doubt for whom the Melachah was done, one is permitted to wash there immediately after Shabbos. According to that opinion, in a place where there is a non-Jewish figure of authority, no other doubt is necessary. Even if the bath was certainly heated on Shabbos, a Jew is permitted to bathe there immediately after Shabbos, since it is possible that it was heated for the Nochri ruler.)

151b----------------------------------------151b

4) POVERTY IS CYCLICAL
AGADAH: The Gemara says that poverty is cyclical, and that it strikes everyone at some point.
(a) The VILNA GA'ON finds an allusion to this in the beginning of Parshas Ki Sisa. The verse states, "v'Nasnu Ish Kofer Nafsho" -- "Every man shall give [a half-Shekel]..." (Shemos 30:12). The Hebrew word "v'Nasnu" ("and he shall give") is a palindrome (a word that can be read the same in both directions, forward and backward). This demonstrates that giving Tzedakah can go both ways. Now it is one person who gives the Tzedakah, but he should be aware that later it might he who is the recipient of the Tzedakah.
Furthermore, the cantillation marks above the word "v'Nasnu" are "Kadma" and "Azla." The names of these cantillation marks literally mean "be early" ("Kadma") and "go" ("Azla"). This, too, alludes to the message of the Gemara here, which tells a person to act soon and early and give his money to Tzedakah while he still has it, before the time comes that he will have to take Tzedakah from others.
(b) Others (see RAMA MI'PANO) point out another allusion to this Gemara from the word "Tzedakah" in that word's "A'T Ba'SH" equivalent. The term "A'T Ba'SH" refers to a method of linguistic extrapolation whereby each letter at one end of the alphabet is replaced with its corresponding letter at the other end of the alphabet (e.g. Alef with Tav, Beis with Shin, and so on).
When the letters that comprise the word "Tzedakah" are exchanged for their "A'T Ba'SH" equivalent, the word "Tzedakah" itself is spelled out backwards! This shows that if a person gives Tzedakah when he prospers, then when circumstances later become reversed and he is in need, Tzedakah comes back to him.

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