Mishnayos Sotah Perek 5 Mishnah 3

Furthermore, on that same day Rabbi Akiva interpreted the verses with regard to the Levite cities as follows: One verse states: “And you shall measure outside the city for the east side two thousand cubits…this shall be for them the open land outside the cities” (Numbers 35:5), and another verse states: “And the open land around the cities, which you shall give to the Levites, shall be from the wall of the city and outward one thousand cubits round about” (Numbers 35:4). It is impossible to say that the area around the cities given to the Levites was only one thousand cubits, as it is already stated: “Two thousand cubits.” And it is impossible to say that two thousand cubits were left for them, as it is already stated: “One thousand cubits.” How can these texts be reconciled? One thousand cubits are to be set aside as a tract of open land surrounding the city, and the two thousand cubits are mentioned not in order to be given to the Levites, but to indicate the boundary of the Shabbat limit, beyond which it is forbidden to travel on Shabbat. This verse thereby serves as the source for the two-thousand-cubit Shabbat limit. Rabbi Eliezer, son of Rabbi Yosei HaGelili, says otherwise: One thousand cubits were given to the Levites as an open tract of land, that could not be planted or built upon, and two thousand cubits of additional land were given to the Levites for planting fields and vineyards.

בּוֹ בַיּוֹם דָּרַשׁ רַבִּי עֲקִיבָא (במדבר לה) וּמַדֹּתֶם מִחוּץ לָעִיר אֶת פְּאַת קֵדְמָה אַלְפַּיִם בָּאַמָּה וְגוֹ', וּמִקְרָא אַחֵר אוֹמֵר (שם) מִקִּיר הָעִיר וָחוּצָה אֶלֶף אַמָּה סָבִיב. אִי אֶפְשָׁר לוֹמַר אֶלֶף אַמָּה, שֶׁכְּבָר נֶאֱמַר אַלְפַּיִם אַמָּה, וְאִי אֶפְשָׁר לוֹמַר אַלְפַּיִם אַמָּה, שֶׁכְּבָר נֶאֱמַר אֶלֶף אַמָּה. הָא כֵיצַד, אֶלֶף אַמָּה מִגְרָשׁ, וְאַלְפַּיִם אַמָּה תְּחוּם שַׁבָּת. רַבִּי אֱלִיעֶזֶר בְּנוֹ שֶׁל רַבִּי יוֹסֵי הַגְּלִילִי אוֹמֵר, אֶלֶף אַמָּה מִגְרָשׁ, וְאַלְפַּיִם אַמָּה שָׂדוֹת וּכְרָמִים: