Siman 377

Previously in siman 357 it was explained that in a chatzer smaller than four amot, it is forbidden to pour water into it on Shabbat unless they made an uka in the chatzer so that the water will fall there; for if not so, the water will go out to the reshut ha-rabim. This is a Mishnah at the end of the eighth chapter of Eruvin (88a), and we learned there: And so too two diota'ot facing one another—and these are two upper stories in a chatzer that do not stand in one row but rather facing one another—some of them made an uka and some of them did not make an uka; those who made an uka are permitted to pour their water, and those who did not make an uka are forbidden. And the Gemara establishes this when they did not make an eruv, for if they had made an eruv between them, both would be permitted; for if there is only an uka, even many homeowners are permitted to pour there, and only when they did not make an eruv are those who did not make an uka forbidden.

And if it is difficult, for when they did not make an eruv what benefit is the uka, for they are forbidden to carry in the hatzer. However, the intention is that those who are permitted do not pour into the hatzer, but rather they pour onto the terrace, and the water descends to the uka adjacent to them. And even though the water goes by his force into the hatzer where carrying is forbidden - they did not decree regarding his force in a hatzer that is not joined by an eruv. But those who did not make an uka - they are forbidden, for we fear that since the uka is far from them - they will not want to pour onto the terrace, from where the water would go to the hatzer and from the hatzer to the uka, which would ruin the hatzer, and they will take their vessels and go to the uka to pour them, and it will be found that they carry in the forbidden hatzer. (Tosafot, the Rosh, and the Ritva)

And behold, according to the opinion of our teachers, we are dealing with a courtyard smaller than four amot, for when there are four amot, there is no need for a pit, as was written in siman 357. However, this does not appear so from the words of the Rambam, who wrote the law of a pit in a courtyard that does not have four amot in the fifteenth chapter of Shabbat, and wrote this law at the end of the fourth chapter of Eruvin, and did not mention at all when there are not four amot in the courtyard. This is the wording of the Rambam: "Two balconies one opposite the other, and one courtyard beneath them into which they pour water—they may not pour until both of them make one eruv. If some of them made a pit in the courtyard to pour the water into it, and some of them did not, those who made it may pour into their pit, and those who did not make it—they may not pour into the courtyard until they make an eruv. And if these made a pit and those made a pit—each of the two may pour into their own pit, even though they did not make an eruv." Thus far his words. And he did not mention a distinction whether the courtyard contains four amot or does not contain them.

It appears to me that the Tosafot, the Rosh, and the Ritva, according to their version of the Mishnah "and so too two stories" - were forced to explain thus, that it refers to the preceding case, to where it does not have four cubits. However, from the wording of the Rambam in the Commentary on the Mishnah and the Bartenura, it is clear that they did not have the version "and so too," (and so wrote the Tosafot Yom Tov) and also in the Mishnah in the Yerushalmi it is not present, see there. And according to this, it is a matter unto itself, and does not pertain to the concern that the water will go to the reshut harabim, but rather due to the prohibition of carrying in the courtyard itself. Therefore, when they did not make an eruv - both are forbidden to pour into the courtyard, and in this there is no novelty at all. And as for what the law is when they pour onto the story and from there it goes to the courtyard - it does not deal with this at all, and the main novelty is when they made a pit, even though the pit is in the courtyard, nevertheless since it is adjacent to the wall of the house - its law is like the house, and it is permitted to pour from the window of the house to the pit. And consequently, the one that did not make a pit must perforce carry via the courtyard - and it is forbidden. And if each one made a pit near their house - each one pours into his own pit, for the law of the pit is like the law of the house. And it can also be said, that when the pit is ten deep - it is a reshut hayachid unto itself, and does not belong to the courtyard at all. And in the Commentary on the Mishnah, the Rambam added another reason as to why the one that did not make a pit is forbidden, because perhaps they will use the courtyard from the dwellings, see there. And it can be said regarding his intention, that even if they want to pour from a distance into the pit, which would have been permitted because it is a domain unto itself - nevertheless it is forbidden for this reason, but from his wording in his composition it implies like the first reason we wrote.

The words of the Tur and Shulchan Aruch are not entirely understood, and this is their wording: "Two upper stories that open to this courtyard, one opposite the other, and one made a pit in the courtyard in order to pour into a courtyard that does not have four cubits its water, and the second did not make one; if they made an eruv together—both are permitted to pour their water. And if they did not make an eruv together, and the one made an eruv for itself and the second did not make an eruv at all, the one that did not make an eruv—is forbidden, and the one that made an eruv—is permitted. Provided that it does not pour directly into the pit, but rather pours in the upper story, and they descend to the pit, for his force in a courtyard that is not joined by an eruv is permitted." Thus far their words. Our teacher, the Rema, wrote that the same law applies if the courtyard is more than four cubits—that both are permitted in such a case, and they do not require a pit. Thus far his words.

And the commentators (Bach and Taz) have already wondered: what benefit is the eruv that this courtyard made for itself? What benefit does the eruv provide for it? Behold, it is forbidden in the courtyard because of the second upper-story, and since the permission is only due to his force—in a courtyard that is not joined by an eruv where it is permitted, why does it need an eruv? Furthermore, behold the reason for the prohibition of the second is because she did not make a pit; if so, what is this that they conclude, "that the prohibition is because she did not make an eruv"? And there is one who wrote that the intention is that since she did not make an eruv for herself—then even if she made a pit she is forbidden, for behold she is forbidden to carry to her balcony without an eruv. Therefore, even if she wants to pour from her house—she is forbidden, for we fear perhaps she will carry to the balcony. (Magen Avraham subsection 1) And it is difficult, for if so, why did they need to say "that one made a pit," let them say that both made a pit. And regarding the essence of the matter, one must also wonder according to the method of the Tosafot: since the primary prohibition from the second is because we fear she will carry the vessel with the water to the pit via the courtyard, if so, what permission is there when the courtyard is more than four cubits? Behold, this concern always exists. (And see Beit Yosef and Taz. And the words of the Levush are completely baffling, as the Taz wondered about him, see there. And the Magen Avraham subsection 2 wrote that if the second made an eruv for herself—the first would have been able to carry in the courtyard and pour directly into the cavity. But when she did not make an eruv—it is "a foot that is forbidden in its place," see there. And it is a wonder, for this applies to the residents of the courtyard and the residents of the balcony, and not to two balconies, for whichever way you look at it, the courtyard belongs to both of them. Furthermore, in truth, who shall compel them to say that this one whose pouring is permitted is by means of his force? Let us say in truth that she can pour into the cavity and that each one made an eruv for herself, for the essence of the law is only that the second is forbidden. And the Magen Avraham himself remained in "needs further study," and also his previous words need further study, see there and delve into it.)

Therefore, it appears in my humble opinion that this is the explanation: for the Tur was troubled by the same difficulty we raised regarding the approach of the Tosafot and the Rosh—what is the relevance of four amot here? Furthermore, regarding the primary concern written by the Tosafot, that the reason it is forbidden for the woman who did not join the eruv to pour onto the balcony because the water will travel through the courtyard to the pit, is because she will be concerned about the ruin of the courtyard and will carry with a vessel to the pit as has been written, we have not found such a decree. Therefore, the Tur explained in a different manner, namely that a courtyard that does not have four amot requires a pit, and without a pit, they are forbidden. When there is a pit, they are permitted even with a thousand residents. This is the reason for the prohibition here for the woman who did not make a pit and did not join the eruv for herself, while the owner of the pit did join the eruv for herself, and based on this they are completely divided from one another, and she is like the owner of another courtyard who has no pit—who is forbidden to pour into the courtyard for the reason that they will go to the public domain. Therefore, the Tur did not mention the concern of the Tosafot, lest she be concerned for the courtyard and carry with the vessel, but rather since she did not join the eruv and did not make a pit, her law remains like a courtyard that does not have four amot and has no pit. But if she too had joined the eruv even for herself, she would nevertheless be considered as one with the owner of the pit, which is not the case when she did not join the eruv at all. (So it appears in my humble opinion, and with this all the difficulties are answered; and examine this carefully.)