1) CAUSING "TUM'AH" TO FRUIT OF ERETZ YISRAEL
QUESTION: Rav Huna (55b) says that once the juice of grapes begins to be drawn away from the grapes, it becomes Yayin Nesech if a Nochri touches it (even before it reaches the Bor). The Gemara questions Rav Huna's ruling from the Mishnah (55a). The Mishnah states that the juice of grapes becomes forbidden (as Yayin Nesech) only after it descends to the pit. Rav Huna answers that the Mishnah is expressing the earlier view, the "Mishnah Rishonah," but the Halachah follows the later view, the "Mishnah Acharonah," which Rav Huna follows. The later Tana (the Mishnah Acharonah) agrees with Rav Huna's law, that once wine starts to flow it becomes Yayin Nesech if a Nochri touches it, and thus one may not stomp wine with a Nochri.
The Mishnah Acharonah also rules that one may harvest with Nochrim, because this Tana maintains that one is permitted to be Metamei produce of Chulin in Eretz Yisrael. This Tana also rules that one may not harvest with a Jew who allows the wine to become Tamei, and all the more so one may not stomp grapes with him.
The contradiction is obvious. If this Tana maintains that one is allowed to be Metamei produce of Eretz Yisrael, why does he state that one may not harvest or stomp on grapes with a Jew who is not careful about Tum'ah? The Jew is doing nothing wrong when he is Metamei the produce!
(a) RASHI (DH v'Ein Botzrin) explains that this Tana does not maintain that one may cause Tum'ah to any produce in Eretz Yisrael. Rather, he maintains only that one may cause Tum'ah to the produce of Nochrim in Eretz Yisrael. Since the produce of a Jew must have Terumah separated from it, and the Terumah must be Tahor, one is forbidden to be Metamei Jewish-owned produce in Eretz Yisrael which is obligated in Terumah.
TOSFOS (DH she'Mutar) asks many questions on Rashi's explanation. The Gemara in Nidah (6b) says that when a woman making dough has a Safek Tum'ah, if she has not yet rolled the dough together and made it obligated in Chalah she should just continue to make the dough, even though she might be Tamei. If she has already created a Chiyuv to separate Chalah, she must ensure that the dough is Tahor. This implies that although something will be Chayav in Chalah (which is equivalent to Terumah), one still may make it when it is Tamei!
Tosfos quotes some who answer that the case in Nidah is different. Flour is not inherently obligated to have Chalah separated from it. Only if one makes a significant amount of dough must Chalah be separated from it. Grapes, however, are always Chayav in Terumah. It therefore makes sense that one may not cause them to become Tamei.
Tosfos does not accept this answer, because the law is that produce does not become obligated in Terumos and Ma'aseros automatically. Only at a certain stage in its processing does it become obligated in Terumos and Ma'aseros, and thus it still should be comparable to the obligation to separate Chalah from dough.
(The IMREI TZVI points out that Tosfos' objection seems problematic. Although the Torah obligation to separate Terumah applies only at a certain stage in its processing, there is an Isur d'Rabanan that prohibits eating the produce with an "Achilas Keva" even before the produce becomes obligated mid'Oraisa in Terumah. This is different from Chalah, where no Chiyuv takes effect whatsoever on the dough unless a certain amount of dough is made.)
(b) Tosfos quotes RABEINU YEHUDAH who found among Rashi's handwritten explanations a different way to learn the Gemara. Rashi wrote that one is permitted to help a Nochri, or help a Jew who is careful with Tum'ah and Taharah, harvest or press grapes when they are Tamei. The problem is in helping a Rasha who is not careful about Tum'ah. Since the Rasha certainly will drink the wine with no concern for Tum'ah or Terumah, one is forbidden to help him. (Y. MONTROSE)
2) "NITZOK CHIBUR" AND CONNECTION THROUGH THE "GARGUSNI"
QUESTION: The Mishnah (55a) states that the juice of the grapes becomes Yayin Nesech only when it reaches the Bor (pit) after the press. Rav Huna explains that this applies only when one did not return the "Gargusni" to the winepress. A Gargusni is a large basket used in winemaking that is suspended above the collection pit, that acts as a filter and strains the juice that flows from the winepress. One removes this filter either when it becomes clogged, or when he wants to place the pieces of grape that are caught in the filter into the press again. Once the filter is returned, it makes all of the juice in the press fit to become Yayin Nesech.
The Gemara asks, why is the juice in the filter fit to be Yayin Nesech? It must be that the law is "Nitzok Chibur," the column of flowing liquid creates a connection (thus connecting the wine in the pit to the wine in the Gargusni, causing the wine in the Gargusni to become prohibited). Since the juice in the Bor gets there from the stream which goes from the Gargusni to the Bor, and what is in the Bor is potential Yayin Nesech, it must be that what is in the Gargusni is also considered potential Yayin Nesech, since it is connected via the stream through Nitzok.
The Gemara answers that the Mishnah does not necessarily maintain that Nitzok Chibur. It may be discussing a case in which the Bor became overfull, and the juice in it touched the bottom of the Gargusni, rendering the juice in the Gargusni potential Yayin Nesech.
TOSFOS (DH Gargusni) asks an obvious question. If the Gemara considers the possibility that the Mishnah maintains Nitzok Chibur, and thus the juice in the Gargusni is fit to become Yayin Nesech, then why does the Mishnah not rule that the juice is potential Yayin Nesech when it is still in the press? Since the wine in the press descends straight into the Gargusni and from there into the Bor, the wine in the press should be considered connected to the wine in the Gargusni which is potential Yayin Nesech, and thus the same Halachah should apply!
(a) TOSFOS answers that although the Halachah is Nitzok Chibur, we do not say "Nitzok Bar Nitzok [Chibur]" -- a column of flowing liquid coming from another column of flowing liquid creates a connection such that the second column has the same Halachic status as the first. Tosfos explains that there is not just one stream which goes straight from the press through the Gargusni and into the Bor. Rather, since the holes in the Gargusni are on the sides of the filter and not on the bottom, the stream of the wine stops for a moment in the Gargusni and then it continues, in the form of a new stream, when it reaches the sides of the filter. Tosfos says that this is the ruling of the RIVAN, RASHBAM, and RABEINU TAM, all in the name of Rashi.
Tosfos adds that this Halachah was applied by Rashi in the following case. A Nochri poured wine from a pitcher into a cup. The wine that entered the cup was clearly forbidden, and the flow that connected the pitcher to the cup made the contents of the pitcher forbidden as well, due to Nitzok Chibur. The Jew then decided to fill up the pitcher again from a barrel of wine. Since the Halachah is Nitzok Chibur, the entire barrel of wine should have become forbidden, since it became connected to the forbidden wine in the pitcher. However, Rashi ruled that the barrel was permitted because it was a case of Nitzok Bar Nitzok, which the Gemara permits.
(b) Tosfos quotes the RIVAM who argues that there is no proof from the Gemara that Nitzok Bar Nitzok is permitted. It is possible that the Mishnah permits the wine in the press because it is not yet considered wine. Why is the wine in the Gargusni forbidden? The Rivam explains that what is on the bottom part of the Gargusni is already considered wine, and therefore can become forbidden by being connected to the Bor through Nitzok. (See Tosfos at length for more discussion on the opinion of the Rivam.) (Y. MONTROSE)