Nedarim 46bChapter 5 HaShuttafin SheNadru

מַחְלוֹקֶת שֶׁיֵּשׁ בָּהּ כְּדֵי חֲלוּקָּה. אֲבָל אֵין בָּהּ כְּדֵי חֲלוּקָּה — דִּבְרֵי הַכֹּל מוּתָּר.

The dispute between Rabbi Eliezer ben Ya’akov and the Rabbis is with regard to a courtyard where there is sufficient area in the courtyard for it to be divided into four square cubits for each partner, so each can be said to have a real portion that can be forbidden to the other. But if there is not sufficient area in it to be divided, everyone agrees that it is permitted to benefit from it, since the entire courtyard is viewed as belonging to both of them and each one can say that he is entering his own portion.

אֲמַר לֵיהּ רַב יוֹסֵף: הֲרֵי בֵּית הַכְּנֶסֶת, דִּכְמִי שֶׁאֵין בּוֹ כְּדֵי חֲלוּקָּה דָּמֵי, וּתְנַן: שְׁנֵיהֶן אֲסוּרִין בְּדָבָר שֶׁל אוֹתָהּ הָעִיר!

Rav Yosef said to Rabba: A synagogue belongs to the entire public and is therefore considered like a courtyard in which there is not sufficient area in it to be divided, and we learned in a mishna later in the chapter (48a) that with regard to two people who vow not to derive benefit from each other, both are prohibited from deriving benefit from an entity belonging to that city such as a synagogue. Evidently, the Rabbis prohibit deriving benefit even from such entities.

אֶלָּא, אָמַר רַב יוֹסֵף, אָמַר זְעֵירִי: מַחְלוֹקֶת שֶׁאֵין בָּהּ כְּדֵי חֲלוּקָּה, אֲבָל יֵשׁ בָּהּ כְּדֵי חֲלוּקָּה — דִּבְרֵי הַכֹּל אָסוּר.

Rather, Rav Yosef said: Ze’eiri must have said: The dispute holds where there is not sufficient area in the courtyard for it to be divided, but if there is sufficient area in it for it to be divided, everyone agrees that it is forbidden, since if either enters it he may be entering the other’s portion.

אָמַר רַב הוּנָא: הֲלָכָה כְּרַבִּי אֱלִיעֶזֶר בֶּן יַעֲקֹב. וְכֵן אָמַר רַבִּי אֶלְעָזָר: הֲלָכָה כְּרַבִּי אֱלִיעֶזֶר בֶּן יַעֲקֹב.

Rav Huna said: The halakha is in accordance with the opinion of Rabbi Eliezer ben Ya’akov. And so too, Rabbi Elazar said: The halakha is in accordance with the opinion of Rabbi Eliezer ben Ya’akov.

הַמּוּדָּר הֲנָאָה מֵחֲבֵירוֹ וְיֵשׁ לוֹ שָׁם מֶרְחָץ וְכוּ׳. וְכַמָּה תְּפִיסַת יָד? אָמַר רַב נַחְמָן: לְמֶחֱצָה לִשְׁלִישׁ וְלִרְבִיעַ. אֲבָל בִּבְצִיר — לָא. אַבָּיֵי אָמַר: אֲפִילּוּ בִּבְצִיר — אָסוּר. הֵיכִי דָּמֵי דִּשְׁרֵי — דִּמְקַבֵּל בְּטַסְקָא.

§ The mishna teaches: With regard to one prohibited by a vow from deriving benefit from another and he has a bathhouse or an olive press in the city that is leased out and available for public use, the forbidden party may use it only if the owner has forfeited his own right to profits from usage. The Gemara asks: And how much is this right to profits from usage that prohibits the subject of the vow from entering the bathhouse? Rav Naḥman said: In cases where he receives one half, one-third, or one-quarter of the profits of the bathhouse. But in a case where he receives less, it is not forbidden. Abaye said: Even in a case where he receives less, it is forbidden. If so, what are the circumstances in which it is permitted and he is not considered to have a right to profits from usage? Where he completely forfeits all profits and receives only an annual rental fee [ taska ] from a tenant.