הלכות עירובין א׳Eruvin 1

Halacha 1א׳

חָצֵר שֶׁיֵּשׁ בָּהּ שְׁכֵנִים הַרְבֵּה כָּל אֶחָד מֵהֶם בְּבַיִת לְעַצְמוֹ דִּין תּוֹרָה הוּא שֶׁיִּהְיוּ כֻּלָּן מֻתָּרִין לְטַלְטֵל בְּכָל הֶחָצֵר וּמִבָּתִּים לֶחָצֵר וּמֵהֶחָצֵר לַבָּתִּים מִפְּנֵי שֶׁכָּל הֶחָצֵר רְשׁוּת הַיָּחִיד אַחַת וּמֻתָּר לְטַלְטֵל בְּכֻלָּהּ. וְכֵן הַדִּין בְּמָבוֹי שֶׁיֵּשׁ לוֹ לֶחִי אוֹ קוֹרָה שֶׁיִּהְיוּ כָּל בְּנֵי הַמָּבוֹי מֻתָּרִים לְטַלְטֵל בְּכֻלּוֹ וּמֵחֲצֵרוֹת לַמָּבוֹי וּמִמָּבוֹי לַחֲצֵרוֹת שֶׁכָּל הַמָּבוֹי רְשׁוּת הַיָּחִיד הוּא. וְכֵן הַדִּין בִּמְדִינָה שֶׁהִיא מֻקֶּפֶת חוֹמָה גְּבוֹהָה עֲשָׂרָה טְפָחִים שֶׁיֵּשׁ לָהּ דְּלָתוֹת וְנִנְעָלוֹת בַּלַּיְלָה שֶׁכֻּלָּהּ רְשׁוּת הַיָּחִיד הִיא. זֶה הוּא דִּין תּוֹרָה:

According to biblical law, if a courtyard has many tenants, each living in a house of his own, they may all move objects throughout the courtyard as well as from the houses into the courtyard and from the courtyard into the houses, because the entire courtyard is a single private domain, so that it is permissible to move objects through the whole of it. The same rule applies to an alley that has courtyards opening into it on three sides and the fourth side opening into the public road. By fastening at this fourth side a stake in the ground or a cross-beam above, the alley and the courts opening into it become a single private domain, so that all the residents of the alley are permitted to transfer objects throughout the alley as well as from the courtyards into the alley and from the alley into the courtyards. And the same is the law in a city that is surrounded by a wall [at least] ten handbreadths tall that has gates that are locked at night, as it is all a private domain. This is the biblical (Torah) law.

Halacha 2ב׳

אֲבָל מִדִּבְרֵי סוֹפְרִים אָסוּר לִשְׁכֵנִים לְטַלְטֵל בִּרְשׁוּת הַיָּחִיד שֶׁיֵּשׁ בָּהּ חֲלוּקָה בְּדִיּוּרִין עַד שֶׁיְּעָרְבוּ כָּל הַשְּׁכֵנִים כֻּלָּן מֵעֶרֶב שַׁבָּת. אֶחָד חָצֵר וְאֶחָד מָבוֹי וְאֶחָד הַמְּדִינָה. וְדָבָר זֶה תַּקָּנַת שְׁלֹמֹה וּבֵית דִּינוֹ:

But by the words of the Scribes it is forbidden for neighbours to carry within a private domain that is divided among separate dwellings until all the neighbours together make an eruv on the eve of the Sabbath. It is all one whether it is a courtyard, an alley or a town. And this matter is an ordinance of Solomon and his court.

Halacha 3ג׳

וְכֵן יוֹשְׁבֵי אֹהָלִים אוֹ סֻכּוֹת אוֹ מַחֲנֶה שֶׁהִקִּיפוּהוּ מְחִצָּה אֵין מְטַלְטְלִין מֵאֹהֶל לְאֹהֶל עַד שֶׁיְּעָרְבוּ כֻּלָּן. אֲבָל שַׁיָּרָא שֶׁהִקִּיפָה מְחִצָּה אֵין צְרִיכִין לְעָרֵב אֶלָּא מוֹצִיאִין מֵאֹהֶל לְאֹהֶל בְּלֹא עֵרוּב לְפִי שֶׁהֵן כֻּלָּן מְעֹרָבִין וְאֵין אוֹתָן אֹהָלִים קְבוּעִין לָהֶן:

And likewise may those dwelling in tents or huts or a camp that they encircled with a partition not carry from one tent to [another] tent until they all make an eruv. But [members] of a caravan that is surrounded by a partition do not need to make an eruv, but may rather transport from one tent to [another] tent without an eruv — since they are all [already] joined together (which is the function of an eruv), and those tents are not permanent [dwellings] for them.