Bava Batra 21b
בבא בתרא כ״א ב — ד"ה אָמַר רַב הוּנָא
Bava Batra 21b:4
Discusses the rights of an established practitioner and the limits on another person’s encroachment. Although the sugya concerns commercial competition, later halakhic reasoning uses its principles in analyzing established communal roles and chazakot.
אָמַר רַב הוּנָא: הַאי בַּר מְבוֹאָה דְּאוֹקִי רִיחְיָא, וַאֲתָא בַּר מְבוֹאָה חַבְרֵיהּ וְקָמוֹקֵי גַּבֵּיהּ – דִּינָא הוּא דִּמְעַכֵּב עִילָּוֵיהּ. דְּאָמַר לֵיהּ: קָא פָּסְקַתְּ לֵיהּ לְחַיּוּתִי. תַּנָּאֵי הִיא, דְּתַנְיָא: כּוֹפִין בְּנֵי מְבוֹאוֹת זֶה אֶת זֶה – שֶׁלֹּא לְהוֹשִׁיב בֵּינֵיהֶן לֹא חַיָּיט, וְלֹא בּוּרְסְקִי, וְלֹא מְלַמֵּד תִּינוֹקוֹת, וְלֹא אֶחָד מִבְּנֵי בַּעֲלֵי אוּמָּנִיּוֹת; וְלִשְׁכֵנוֹ אֵינוֹ כּוֹפֵיהוּ. רַבָּן שִׁמְעוֹן בֶּן גַּמְלִיאֵל אוֹמֵר: אַף לִשְׁכֵנוֹ כּוֹפֵיהוּ.
§ Rav Huna said: There was a certain resident of an alleyway who set up a mill in the alleyway and earned his living grinding grain for people. And subsequently another resident of the alleyway came and set up a mill next to his. The halakha is that the first one may prevent him from doing so if he wishes, as he can say to him: You are disrupting my livelihood by taking my customers. The Gemara answers: This entire matter is a dispute between tanna’im, as it is taught in a baraita: The residents of an alleyway can compel one another to agree not to allow among them in that alleyway a tailor, a tanner, a teacher of children, nor any type of craftsman. They can bar outside craftsmen from plying their trade in that alleyway. But one cannot compel his neighbor, i.e., one who already lives in the alleyway, to refrain from practicing a particular occupation there. Rabban Shimon ben Gamliel says: One can even compel his neighbor not to conduct such work in the alleyway. Rav Huna holds in accordance with the opinion of Rabban Shimon ben Gamliel.
