Talmud - Eruvin 94b עירובין צ״ד ב׳

and with a case where the courtyard was breached in a corner, so that it is breached on two sides. Although the opening is no more than ten cubits wide, it cannot be considered an entrance, as people do not build an entrance in a corner. It is therefore clear that this is a breach that negates the partition.

We learned in the mishna: And likewise, with regard to a house that was breached on Shabbat from two of its sides into a public domain, the residents are permitted to carry in the house on that Shabbat, but not a future Shabbat. The Gemara asks: In what way is a breach on one side different? The difference is due to the fact that we say: The edge of the roof descends and seals the house, as if there were a full-fledged partition there. So too, when it is breached on two sides, let us say: The edge of the roof descends and seals.

The Gemara answers: The Sages of the school of Rav said in the name of Rav: The mishna is referring to a case where the house was breached in a corner, and its roofing was inclined, as in that case, one cannot say: The edge of the roof descends and seals, as the edge of an inclined roof does not appear to be the beginning of a partition.

And Shmuel said: The mishna is referring to a breach that is even wider than ten cubits. The Gemara asks: If so, why did the mishna cite a case where it is breached from two sides? It should be prohibited to carry there even if it were breached from one side.

The Gemara answers: The reason that it is prohibited only if it is breached from two sides is due to the fact that it is a house. In the case of a courtyard, the same halakha would apply even if it were breached on only one side. However, the mishna sought to teach the halakha of a house as well, in which case, it is prohibited to carry only if it is breached on two sides. If it is breached on one side, the edge of the roof descends and seals, and carrying is permitted.

The Gemara asks: But the halakha of a house itself should pose a difficulty according to this explanation. In what way is a breach on one side different? It is due to the fact that we say: The edge of the roof descends and seals the house, as if there were a full-fledged partition there. So too, when it is breached on two sides, let us say: The edge of the roof descends and seals.

And furthermore: Is Shmuel of the opinion that there is a principle: The edge of a roof descends and seals? But wasn’t it stated that there is an amoraic dispute with regard to a portico located in a valley, which has the status of a karmelit. Rav said: It is permitted to carry in the entire portico, as he maintains that the edge of the roof of the portico descends and seals, rendering it a private domain. And Shmuel said: One may carry only within four cubits. Apparently, Shmuel does not accept the principle: The edge of a roof descends and seals.

The Gemara answers: This is not a difficulty. Where Shmuel is not of the opinion that this principle is applied, it is with regard to a structure where walls on all four sides are formed in that manner. However, with regard to a structure where only three sides are formed in that manner and the fourth side is an actual wall, he is of the opinion that the principle is applied.

The Gemara comments: In any case, this is difficult. Although the contradiction between the two statements of Shmuel was resolved, the question remains: Why do we not apply the principle: The edge of a roof descends and seals, to two sides of the house?

The Gemara answers: The reason is as the Sages of the school of Rav said in the name of Rav: The mishna is referring to a case where the house was breached in a corner, and its roofing was inclined, as in that case, one cannot say: The roof of the house descends and seals. Here too, Shmuel’s opinion can be explained in a similar manner: The mishna is dealing with a case where the house was breached in a corner, and its roof is at a distance of at least four handbreadths from the breach, and is uneven. In that case, the principle: The edge of a roof descends and seals, would have to be applied to four corners, and Shmuel is of the opinion that it may not be applied in that case.

The Gemara explains: Shmuel did not say his explanation of the mishna in accordance with the opinion of Rav, as the mishna does not teach that the roof was slanted, which is the crux of Rav’s explanation. And Rav did not say his explanation of the mishna in accordance with the opinion of Shmuel, as if so, even if the roof was breached on several sides, its legal status would be that of a portico, and Rav conforms to his standard line of reasoning, as he said: With regard to a portico, it is permitted to carry throughout the entire portico.

The Gemara proceeds to cite the dispute between Rav and Shmuel in a more comprehensive manner. As it was stated that Rav said: It is permitted to carry in the entire portico as it is considered sealed. And Shmuel said: One may carry only within four cubits. As the portico does not have actual partitions it is subsumed into the field, and shares its status of a karmelit.

The Gemara elaborates on their respective opinions. Rav said: It is permitted to carry in the entire portico, as he maintains that we say: The edge of the roof descends and seals the portico to form a partition. As there is a roof over the portico, it is considered sealed with partitions on all four sides. And Shmuel said: One may carry only within four cubits, as we do not say: The edge of the ceiling descends and seals.

The Gemara elaborates further: If the openings on the sides of the portico are no wider than ten cubits, everyone agrees that they are considered sealed, as the status of even an unroofed breach of ten cubits or less is that of an entrance, and one is permitted to carry throughout the entire domain. They disagree only in a case where the openings are more than ten cubits wide.

And some say: On the contrary, if the openings are more than ten cubits wide, everyone agrees that they are considered breaches, and the principle: The edge of the roof descends and seals, is not applied. They disagree only in a case where the openings are no wider than ten cubits.

And that which Rav Yehuda said:

Traduction : The William Davidson digital edition of the Koren Noé Talmud, with commentary by Rabbi Adin Even-Israel Steinsaltz.

Eruvin 94b examines how breaches on one or two sides of a courtyard or house affect the validity of partitions permitting carrying on Shabbat.