סימן צד סעיף ב

שְׁתֵּי חֲצֵרוֹת שֶׁיֵּשׁ בֵּינֵיהֶם פֶּתַח, אִם רוֹצִים, עוֹשִׂים כָּל בְּנֵי חָצֵר עֵרוּב אֶחָד בִּפְנֵי עַצְמָם, וּמֻתָּרִים כָּל בְּנֵי הֶחָצֵר לְטַלְטֵל בֶּחָצֵר שֶׁלָּהֶם. אֲבָל אֲסוּרִים לְטַלְטֵל מֵחָצֵר לֶחָצֵר כֵּלִים שֶׁשָׁבְתוּ בַּבָּיִת. וְאִם רוֹצִים, עוֹשִׂים כָּל הַדָּרִים בִּשְׁתֵּי חֲצֵרוֹת, עֵרוּב אֶחָד, כְּדֵי שֶׁיִּהְיוּ מֻתָּרִין לְטַלְטֵל גַּם מֵחָצֵר לְחָצֵר אֲפִלּוּ כֵּלִים שֶׁשָׁבְתוּ בַּבָּיִת. וְאִם יֵשׁ בֵּין הַחֲצֵרוֹת אֲפִלּוּ רַק חַלּוֹן שֶׁהוּא לְכָל הַפָּחוֹת רָחָב אַרְבָּעָה טְפָחִים וְגָבוֹהַּ אַרְבָּעָה טְפָחִים וְהוּא בְּתוֹךְ עֲשָׂרָה טְפָחִים סָמוּךְ לָאָרֶץ וְאֵין בּוֹ סְרִיגָה, גַּם כֵּן יְכוֹלִין לְעָרֵב בְּיַחַד. אֲבָל בְּפָחוֹת מִזֶּה, אֵין יְכוֹלִין לְעָרֵב בְּיָחַד. וְאִם יֵשׁ חַלּוֹן בֵּין שְׁנֵי בָּתִּים, אֲפִלּוּ הוּא גָּבוֹהַּ לְמַעְלָה מֵעֲשָׂרָה טְפָחִים, יְכוֹלִין לְעָרֵב בְּיַחַד (מִשּׁוּם דְּבֵיתָא כְּמָאן דְּמַלְיָא דָּמִי) (שעב).

When two courtyards have a door between them, if they wish, all the tenants of each courtyard may make a separate eiruv, whereby all the tenants of the courtyard are permitted to carry into their own courtyard; but any vessels that were in the house before Shabbos began,⁵But vessels that were in the court at the beginning of Shabbos may be carried from one court into the other. [Mishnah Berurah 372: 13] are forbidden to be carried from one courtyard into the other.⁶If you did take out an article from a house to the court without an eiruv you may not move the article four amos in the court. See Mishnah Berurah 372: 16 and Biur Halachah. If they wish, all the tenants of both courtyards can make one eiruv jointly, in order that they should be allowed to carry, from one courtyard into the other, even such vessels that were in the house when Shabbos began. And if there is even a window between the courtyards that measures no less than four tefachim wide by four tefachim high,⁷Four by four square. If the window is round it must be large enough so that a four by four [tefachim] square can be inscribed in it. That puts the diameter of the window at 5 3/5 tefachim. See Sha’ar Hatziyun 372: 18—Rambam etc. and it is within ten⁸Part of it has to be within ten tefachim. That part must be four tefachim wide. [Shulchan Aruch 372: 4, Eliyahu Rabbah, Mishnah Berurah] tefachim above the ground, and it has no grate,⁹Rema 372: 5. There must be an unobstructed empty space of four by four tefachim. [Mishnah Berurah— Acharonim] [the tenants of both courtyards] may also make a joint eiruv. But if it is less than that, they cannot make a joint eiruv. If there is a window between two houses, even if it is higher than ten tefachim, they can make a joint eiruv, (because the house is considered as filled).¹⁰And thus the window is not considered to be ten tefachim high. [Mishnah Berurah 372: 34]

תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)