OPINIONS: The Gemara relates that when Reish Lakish went to Batzra, he saw the Jewish residents drinking from public water sources. He told the people that they must stop drinking the public water, which the idolaters worshipped. When he returned and related the incident to Rebbi Yochanan, Rebbi Yochanan told him that he should go back and tell the people that he had made a mistake, and that they indeed were allowed to drink the water. The Gemara initially assumes that Rebbi Yochanan ruled this way because of his view that idolaters cannot forbid public water.

The Gemara asks that perhaps Rebbi Yochanan's reasoning in this case was that the water was considered attached to the ground when it was worshipped (in a canal or stream), and something attached to the ground cannot become forbidden (45a). The Gemara answers that this could not have been Rebbi Yochanan's reasoning, because in Batzra, the water was outside the stream, like a wave of water which is not always considered attached to the water from which it comes.

The Gemara says that this approach resolves a question of the Gemara earlier (46a). Rebbi Yochanan and the sons of Rebbi Chiya disagree about whether or not rocks that naturally become detached from a mountain become forbidden when a Nochri bows down to them. One opinion maintains that they do not become forbidden, since, like a mountain (which cannot become forbidden), they were never handled as a movable object. The other opinion maintains that the rocks become forbidden since there are no longer attached to the ground. The Gemara there is in doubt about which Amora said which opinion. The Gemara here suggests that we may conclude that it is Rebbi Yochanan who maintains that the rocks are forbidden, since he says that water which becomes detached can become forbidden by a Nochri. The Gemara responds that in the case of the water, the Nochri touched the water with his hand, and that is why it is forbidden.

Why does the Nochri's touch make the water forbidden?

(a) The RA'AVAD says that the Gemara is saying that Rebbi Yochanan permits the water even if a Nochri splashed the water upwards, detaching it from its source, and then bowed down to the water when it was in mid-air. Rebbi Yochanan maintains that water of the public is always permitted, even if it is not considered attached to the ground.

(b) The Ra'avad quotes others who explain that the Gemara's answer, that one touched the water, does not refer to a Nochri who touched the water, but rather to a Jew who takes some water out of the stream, and then a Nochri worships that water. Since the water is still considered the water of the public, the Nochri cannot forbid the water. This is similar to the rule that a person cannot forbid something which is not his.

The Ra'avad questions this explanation. Is it possible that the Gemara means that the novel ruling of Rebbi Yochanan, that a Nochri cannot prohibit public water, is simply because the water is not his? It is obvious that a person cannot forbid water over which he does not have full ownership! Moreover, if this indeed is the basis for Rebbi Yochanan's ruling, then the Gemara should say that even in a case of partners Rebbi Yochanan maintains that the water does not become forbidden. Why does it answer that the case is where "he touched it with his hand"?

The AVODAH BERURAH points out that the RASHBA (53b) writes in the name of the RAMBAN that this explanation does not mean that Rebbi Yochanan is teaching that a person cannot forbid something when he is only a partner in the ownership of that object. When Rebbi Yochanan says that the public water is shared by everyone, he is teaching that no one really owns it, since everyone has a right to use it. The Gemara therefore could not have answered that Rebbi Yochanan maintains that even a partner cannot forbid a jointly-owned object; Rebbi Yochanan never referred to the laws of partners in this case. (Y. MONTROSE)

OPINIONS: The Gemara relates that a Nochri dropped his Esrog into a barrel of Jewish wine. The Nochri stretched out his hand to retrieve his Esrog. Rav Ashi said that they should grab the Nochri's hand and hold it still in the barrel, while they spill out the wine into another vessel, in order that the Nochri not shake (Shichshuch) the wine and render it forbidden from benefit.

Why would the wine be permitted to drink if Jews hold the Nochri's hand steady in the barrel? Since the Nochri knowingly put his hand into a barrel of wine, the wine should be forbidden!

(a) RASHI (DH u'Birtzuha) writes that the Nochri's hand had to be held still so that he would not shake the wine, which would make the barrel forbidden from benefit. Even if Jews would hold his hand and take it out of the wine, it would be impossible to guard against the Nochri wiggling his hand a little and being Menasech the wine.

What does Rashi mean when he says (DH Ki Heichi) that wine becomes forbidden from benefit only through shaking? What is the Halachah, according to Rashi, when a Nochri touches the wine but clearly does not shake it?

1. The TOSFOS RID explains that according to Rashi, the wine does not become forbidden from benefit if the Nochri was unable to shake it.

2. The RITVA understands that when Rashi says that the wine becomes forbidden only through Shichshuch, he is referring to a case such as the Esrog case, where the contact with the wine was initiated "she'Lo b'Kavanah," without intent. If a Nochri touches Jewish wine with intent, it becomes forbidden from benefit even without Shichshuch.

(b) TOSFOS (DH Naktuha) quotes RABEINU TAM who says that in the case of the Gemara, the Nochri thought that the barrel was full of oil, not wine. A similar case is discussed earlier (58a), where the Gemara says that the wine may be sold. Such a case is included in the category of "she'Lo b'Kavanah."

(c) Tosfos quotes the RASHBAM who says that although the Nochri knew that the barrel contained wine, he had no intention to stick his hand in the wine, but only to save his Esrog. Accordingly, it is considered as though he thought it was oil. However, once he saves his Esrog, he is now considered as knowingly touching the wine, which is why his hand must be held to prevent Shichshuch. (Y. MONTROSE)