Eruvin 43

להבריח מים עשויות

for they are only made to keep the water out; that is to say, a boat’s walls are not designed to turn it into a place of residence, but to protect it from the water. Therefore, they do not have the status of partitions made for the purpose of residence.

ורבה מאי טעמא לא אמר כרבי זירא במהלכת כולי עלמא לא פליגי כי פליגי בשעמדה

The Gemara asks: As for Rabba, what is the reason he did not state his opinion in accordance with the opinion of Rabbi Zeira? The Gemara answers: With regard to a boat that is moving, all agree, i.e., even Rabbi Yehoshua and Rabbi Akiva, that one is permitted to walk about the entire boat. They disagree only with regard to a boat that is stationary. Rabban Gamliel holds that the boat’s walls constitute effective partitions, whereas Rabbi Yehoshua disagrees.

אמר רב נחמן בר יצחק מתניתין נמי דיקא דבמהלכת לא פליגי ממאי מדקתני מעשה שבאו מפלנדרסין והפליגה ספינתם בים רבן גמליאל ורבי אלעזר בן עזריה הלכו את כולה ורבי יהושע ורבי עקיבא לא זזו מארבע אמות שרצו להחמיר על עצמן

Rav Naḥman bar Yitzḥak said: The mishna is also precise in its implication that the tanna’im do not disagree with regard to a moving boat. The Gemara asks: From where is this implied? From that which is taught: There was an incident where all of these Sages were coming from Pelandarsin, and their boat set sail on the sea on Shabbat, taking them out beyond their Shabbat limit. Rabban Gamliel and Rabbi Elazar ben Azarya walked about the entire boat, while Rabbi Yehoshua and Rabbi Akiva did not move beyond four cubits, as they sought to be stringent with themselves.

אי אמרת בשלמא במהלכת לא פליגי היינו דקתני רצו דילמא עמדה

Rav Naḥman bar Yitzḥak explains: Granted, if you say that they do not disagree with regard to a moving boat, that is why it is taught that they sought to be stringent with themselves, i.e., they wished to practice stringency although they were under no obligation to do so, as they were concerned that perhaps the boat will stand, i.e., come to a stop.

אלא אי אמרת פליגי האי רצו להחמיר איסורא הוא

But if you say that they disagree even in the case of a boat that is moving, this phrase: Sought to be stringent, is problematic, for the mishna should not refer to a desire to be stringent, as according to their opinion it is an outright prohibition.

אמר רב אשי מתניתין נמי דיקא דקתני ספינה דומיא דדיר וסהר מה דיר וסהר דקביעי אף ספינה נמי דקביעא

With regard to the previous issue, Rav Ashi said: The mishna is also precise, implying this point in another manner as well, for it teaches the law governing a boat parallel to the law governing a pen and a stable. Just as a pen and a stable are fixed in their place, so too, the mishna discusses a boat that is fixed in its place.

אמר ליה רב אחא בריה דרבא לרב אשי הלכתא כרבן גמליאל בספינה הלכתא מכלל דפליגי

Rav Aḥa, son of Rava, said to Rav Ashi: Rav and Shmuel both said that the halakha is in accordance with Rabban Gamliel with regard to a boat, and if they had to decide the halakha, then this proves by inference that the tanna’im disagreed about the issue. This is difficult, as the words: They wished to be stringent upon themselves, imply that there was no fundamental dispute at all.

אין והתניא חנניא (בן אחי רבי יהושע) אומר כל אותו היום ישבו ודנו בדבר הלכה אמש הכריע אחי אבא הלכה כרבן גמליאל בספינה והלכה כרבי עקיבא בדיר וסהר:

Rav Ashi replied: Yes, the tanna’im do in fact disagree about a boat that is standing. When the mishna says that Rabbi Yehoshua and Rabbi Akiva wished to be stringent upon themselves, implying that there is no real dispute, it is referring to a boat that is stationary. And it was taught in a baraita: Ḥananya, son of Rabbi Yehoshua’s brother, says: All that day they spent on the boat, they sat and discussed the matter of halakha; and come evening my father’s brother, i.e., Rabbi Yehoshua, determined: The halakha is in accordance with the opinion of Rabban Gamliel with regard to a moving boat, i.e., one is permitted to walk about all of it. And the halakha is in accordance with the opinion of Rabbi Akiva with regard to a pen and a stable, i.e., one may only walk four cubits in them, and the same applies to a stationary boat.

בעי רב חנניא יש תחומין למעלה מעשרה או אין תחומין למעלה מעשרה

Rav Ḥananya raised a dilemma: Does the prohibition of Shabbat limits apply above ten handbreadths from the ground, or perhaps does the prohibition of Shabbat limits not apply above ten handbreadths? In other words, does the Shabbat limit apply only close to the ground, in which case walking more than ten handbreadths above the ground, would be permitted?

עמוד גבוה עשרה ורחב ארבעה לא תיבעי לך דארעא סמיכתא היא

The Gemara clarifies the case in which this dilemma arises: With regard to a post ten handbreadths high and four handbreadths wide, partly within the limit and partly outside of it, this case should not be a dilemma for you. Such a stable post is like solid ground, although it differs from the surrounding area in height; therefore, it is prohibited to walk from the part within the limit to the part outside of it.

כי תיבעי לך בעמוד גבוה עשרה ואינו רחב ארבעה אי נמי דקאזיל בקפיצה

The case where there should be a dilemma for you is that of a post ten handbreadths high but not four handbreadths wide, or the like. Alternatively, the case is one where he advances by way of a leap in the air above ten handbreadths from the ground.

לישנא אחרינא בספינה מאי

The Gemara presents another version of the previous dilemma: What is the halakha with regard to a boat sailing on the surface of the water more than ten handbreadths from the sea or river bed? Does the prohibition of Shabbat limits apply or not?

אמר רב הושעיא תא שמע מעשה שבאו מפלנדרסין והפליגה ספינתם בים וכו׳ אי אמרת בשלמא יש תחומין משום הכי רצו אלא אי אמרת אין תחומין אמאי רצו

Rav Hoshaya said: Come and hear a resolution to this dilemma from what was taught in the mishna: It once happened that all of these Sages were coming from Pelandarsin, and their boat set sail on the sea, etc. Granted, if you say that the prohibition of Shabbat limits applies above ten handbreadths, this is why Rabbi Yehoshua and Rabbi Akiva sought to be stringent. However, if you say that the prohibition of Shabbat limits does not apply above ten handbreadths, why did they seek to be stringent?

כדאמר רבא במהלכת ברקק הכא נמי במהלכת ברקק

The Gemara answers: It may be suggested as Rava said with regard to a parallel case, establishing that case as one where the boat was moving through shallow, swampy water; here, too, we are dealing with a case where the boat was moving through shallow, swampy water, within ten handbreadths of the sea’s bed, so that the prohibition of Shabbat limits certainly applies.

תא שמע פעם אחת לא נכנסו לנמל עד שחשיכה וכו׳ אי אמרת בשלמא יש תחומין שפיר אלא אי אמרת אין תחומין כי לא היינו בתוך התחום מאי הוי

The Gemara cites another proof. Come and hear a resolution from the mishna: On one occasion on a Shabbat eve, they did not enter the port until after nightfall, etc. Granted, if you say that the prohibition of Shabbat limits applies above ten handbreadths, it was well that they asked whether or not they may disembark. However, if you say that the prohibition of Shabbat limits does not apply above ten handbreadths, even if Rabban Gamliel had told them: We were not within the city’s limit before nightfall, what difference would it have made? They could have alighted from the boat, for the boat was above ten handbreadths, where the prohibition of Shabbat limits does not apply.

אמר רבא במהלכת ברקק

The Gemara answers that Rava said: The mishna refers to a case where the boat was moving through shallow, swampy water within ten handbreadths of the sea’s bed.

תא שמע הני שב שמעתא דאיתאמרן בצפרא בשבתא קמיה דרב חסדא בסורא בהדי פניא בשבתא קמיה דרבא בפומבדיתא

The Gemara cites another proof: Come and hear a resolution from the incident involving the seven teachings that were first said on Shabbat morning before Rav Ḥisda in Sura and then repeated toward the conclusion of that Shabbat before Rava in Pumbedita, despite the fact that the distance between them is too great for someone to have traversed it on Shabbat.

מאן אמרינהו לאו אליהו אמרינהו אלמא אין תחומין למעלה מעשרה לא דלמא יוסף שידא אמרינהו

Who said those teachings, and delivered them from one place to the other? Was it not Elijah the Prophet, who traveled from Sura to Pumbedita by way of a miraculous leap through the air above ten handbreadths from the ground, who said them? Apparently, the prohibition of Shabbat limits does not apply above ten handbreadths, for Elijah would not have transgressed this prohibition. The Gemara rejects this argument: This is no proof; perhaps Yosef the demon, who does not observe Shabbat, reported these teachings and brought them from Sura to Pumbedita.

תא שמע הריני נזיר ביום שבן דוד בא מותר לשתות יין בשבתות ובימים טובים

The Gemara attempts to bring a different proof: Come and hear that which was taught in a baraita: With regard to one who said: I will be a nazirite on the day that the son of David comes, i.e., upon the arrival of the Messiah, he is permitted to drink wine on Shabbat and Festivals, for the Messiah will not arrive on one of those days.

ואסור לשתות יין כל ימות החול

However, he is prohibited to drink wine on all weekdays, in case the Messiah has come and he has not yet been informed.

אי אמרת בשלמא יש תחומין היינו דבשבתות ובימים טובים מותר אלא אי אמרת אין תחומין בשבתות ובימים טובים אמאי מותר

The Gemara clarifies: Granted, if you say that the prohibition of Shabbat limits applies above ten handbreadths, that is why on Shabbat and Festivals he is permitted to drink wine, for the Messiah will certainly not arrive from outside the Shabbat limit on those days. But if you say that the prohibition of Shabbat limits does not apply above ten handbreadths, why is he permitted to drink wine on Shabbat and Festivals?

שאני התם דאמר קרא הנה אנכי שלח לכם את אליה הנביא וגו׳ והא לא אתא אליהו מאתמול

The Gemara answers: It is different there, as the verse stated: “Behold I will send you Elijah the prophet, before the coming of the great and dreadful day of the Lord; and he shall turn the heart of the fathers to the children, and the heart of the children to their fathers” (Malachi 3:23–24). This verse teaches that Elijah will arrive the day before the coming of the Messiah. Since Elijah did not come the previous day, the Messiah will not come today, and therefore he may drink.

אי הכי בחול כל יומא ויומא נמי לישתרי דהא לא אתא אליהו מאתמול אלא אמרינן לבית דין הגדול אתא הכא נמי לימא לבית דין הגדול אתא

The Gemara rejects this argument: If so, on weekdays, too, he should be permitted to drink wine each and every day, as Elijah did not arrive the previous day. Rather, the reason for the prohibition on weekdays must be that we say that Elijah may already have arrived at the Great Court, but it has not yet become a matter of public knowledge. Likewise, here too we should say that Elijah already arrived the previous day at the Great Court, on the eve of Shabbat or a Festival.

כבר מובטח להן לישראל שאין אליהו בא לא בערבי שבתות ולא בערבי ימים טובים מפני הטורח

The Gemara answers: It has already been promised to the Jewish people that Elijah will not come either on the eve of Shabbat or on the eve of a Festival, due to the trouble, lest people go out to greet him and not have time to complete all their preparations for the sacred day.

קא סלקא דעתך מדאליהו לא אתא משיח נמי לא אתי במעלי שבתא לישתרי אליהו לא אתי משיח אתי דכיון דאתי משיחא הכל עבדים הן לישראל

The Gemara comments: It might enter your mind to say that since Elijah will not come on Shabbat eve due to the trouble involved, the Messiah will also not come then, and if so, on Shabbat eve he should also be permitted to drink wine. However, this reasoning is rejected: It is only Elijah who will not arrive on Shabbat eve, but the Messiah himself may arrive, for once the Messiah comes, all the nations will be subservient to the Jewish people, and they will help them prepare whatever is needed for Shabbat.

בחד בשבא לישתרי לפשוט מינה דאין תחומין דאי יש תחומין בחד בשבא לישתרי דלא אתא אליהו בשבת

The Gemara raises a difficulty: He should be permitted to drink wine on a Sunday, for if Elijah cannot come on Shabbat, the Messiah will not come on a Sunday. Let us resolve from here that the prohibition of Shabbat limits does not apply above ten handbreadths, as if the prohibition of Shabbat limits applies above ten handbreadths, on Sunday he should be permitted to drink wine, as Elijah cannot come on Shabbat.

האי תנא ספוקי מספקא ליה אי יש תחומין או אין תחומין ולחומרא

The Gemara answers: This tanna was uncertain whether there is a prohibition of Shabbat limits above ten handbreadths or there is no prohibition of Shabbat limits. Therefore, he ruled stringently in this regard concerning Sunday.

דקאי אימת דקא נדר אילימא דקאי בחול כיון דחל עליה נזירות היכי אתיא שבתא ומפקעא ליה

The Gemara poses a question: When did the person who took the vow of naziriteship arise and take his vow? If you say he arose and took his vow on a weekday, since the vow of naziriteship already took effect, how can Shabbat come and annul it? Naziriteship cannot take effect one day and be annulled on the next; rather, once it applies, it remains in effect for the entire period of his vow.

אלא דקאי בשבתא וקא נדר וביום טוב וקא נדר וההוא יומא דשרי ליה מיכן ואילך אסיר ליה:

Rather, it must be that he arose on Shabbat and took his vow, or else he arose on a Festival and took his vow, and it is only on that day that he is permitted to drink wine, as the Messiah will not come; but from that day on he is prohibited to drink wine, for once the naziriteship takes effect on a weekday, it remains in effect from that point onwards, even on Shabbat and Festivals.

פעם אחת לא נכנסו לנמל וכו׳:

It was taught in the mishna: On one occasion, they did not enter the port until after nightfall on Shabbat eve, and they asked Rabban Gamliel whether they were permitted to alight from the boat. He told them that they were permitted to alight, for he had been watching, and he knew that they had entered within the city’s limit before nightfall, and therefore they may walk throughout the city.

תנא שפופרת היתה לו לרבן גמליאל שהיה מביט וצופה בה אלפים אמה ביבשה וכנגדה אלפים בים

In order to clarify this issue, the Gemara cites that which was taught in a baraita: Rabban Gamliel had a special tube through which he would look and see a distance of two thousand cubits on land, and also determine a corresponding distance of two thousand cubits at sea.

הרוצה לידע כמה עומקו של גיא מביא שפופרת ומביט בה וידע כמה עומקו של גיא

In general, one who wishes to know the depth of a valley can bring such a tube and look through it, and he will know the depth of the valley.

והרוצה לידע כמה גובהו של דקל מודד קומתו וצלו וצל קומתו וידע כמה גובה של דקל

The Gemara cites another statement with regard to measurements: One who wishes to know the height of a palm tree, but does not want to actually climb the tree to measure it, can measure his own height, and the length of his own shadow, and the length of the shadow of the height of the palm tree, and calculate the proportions, and he will know the height of the palm tree.

הרוצה שלא תשרה חיה רעה בצל קבר נועץ קנה בארבע שעות ביום ויראה להיכן צלו נוטה משפיע ועולה משפיע ויורד

The Gemara cites related advice: If, out of honor for the dead, one wishes that a wild beast should not rest in the shade of a grave, he should insert a reed into the ground at the end of the fourth hour of the day, roughly ten o’clock in the morning, when it is hot in the sun and cooler in the shade, and beasts begin to seek shelter in the shade. And he should observe in which direction the shadow of the reed inclines, and then slant the gravestone upwards and downwards until he finds an angle at which it casts no shadow at that hour, and the beasts will not come to rest at the grave during the heat of the day.

נחמיה בריה דרב חנילאי משכתיה שמעתא ונפק חוץ לתחום אמר ליה רב חסדא לרב נחמן נחמיה תלמידך שרוי בצער

The Gemara relates that Neḥemya, son of Rav Ḥanilai, was once so engrossed in his learning that he did not notice that he was going out beyond his Shabbat limit. Rav Ḥisda said to Rav Naḥman: Your student Neḥemya is in distress, as he is outside the Shabbat limit and cannot enter. What can we do for him?

אמר לו עשה לו מחיצה של בני אדם ויכנס

Rav Naḥman said to him: Establish a human partition for him, i.e., people who are permitted to go out there should line up and form human walls, through which he is permitted to walk and thereby reenter the Shabbat limit.

יתיב רב נחמן בר יצחק אחוריה דרבא ויתיב רבא קמיה דרב נחמן אמר ליה רב נחמן בר יצחק לרבא מאי קא מבעיא ליה לרב חסדא

Rav Naḥman bar Yitzḥak sat behind Rava, and Rava sat in the first row before Rav Naḥman. Rav Naḥman bar Yitzḥak said to Rava: What precisely was Rav Ḥisda’s dilemma that he addressed to Rav Naḥman with regard to Neḥemya’s distress?

אילימא בדמלו גברי עסקינן וקא מבעיא ליה הלכתא כרבן גמליאל

The Gemara explains: If you say that we are dealing with a case where the space between Neḥemya and the Shabbat limit could be filled with people who had established an eiruv and were permitted to go out beyond the Shabbat limit and establish a human partition for Neḥemya, and then it can be argued that the dilemma that he raised was: Is the halakha in accordance with the opinion of Rabban Gamliel that a person may walk throughout an enclosed area, although he had not established residence there before Shabbat while it was still day, and the same applies to a human partition of this kind;