סימן קלה סעיף ט
יָרְדוּ גְשָׁמִים, פָּטוּר מִן הַסֻכָּה. בְּאֵיזֶה גְשָׁמִים פָּטוּר? אִם יָרְדוּ כָּל כָּךְ, שֶׁהוּא מְשַׁעֵר, שֶׁאִם הָיוּ נוֹפְלִים כָּךְ לְתוֹךְ הַתַּבְשִׁיל, הָיָה מִתְקַלְקֵל, אֲפִלּוּ אֵין לְפָנָיו הַתַּבְשִׁיל, אוֹ שֶׁהוּא מְשַׁעֵר, שֶׁאִם הָיוּ נוֹפְלִים לְתוֹךְ הַחֶדֶר שֶׁהוּא בּוֹ, הָיָה יוֹצֵא מִשָּׁם לְחֶדֶר אַחֵר, אָז יוֹצֵא גַּם מִן הַסֻּכָה לַבָּיִת. וְאִם הִתְחִיל לֶאֱכֹל בַּסֻּכָּה, וְאַחַר כָּךְ יָרְדוּ גְשָׁמִים וְנִכְנַס לְתוֹךְ הַבַּיִת, וְהִתְחִיל לֶאֱכֹל גַּם בַּבַּיִת, אוֹ שֶׁמֵּחֲמַת הַגְּשָׁמִים הִתְחִיל מִתְּחִלָּה לֶאֱכֹל בַּבַּיִת, וְאַחַר כָּךְ פָּסְקו הַגְשָׁמִים, גוֹמֵר סְעוּדָתוֹ בַּבַּיִת וְאֵינוֹ מְחֻיָב לָלֶכֶת בְּאֶמְצַע הַסְּעוּדָה מִבֵּיתוֹ לְתוֹךְ הַסֻּכָּה. וְכֵן כְֹּשֶהָעֵת קַר וְהַמַּאֲכָלִים נִקְרָשִׁים בְּתוֹךְ הַסֻּכָּה, פָּטוּר מִן הַסֻּכָּה וְאוֹכֵל בַּבָּיִת.
If it rains, you are exempt from [staying in] the sukkah.10However, if the rain does not drip through to the place where you are sitting, you must remain in the sukkah until it rains on you and on the table where you are sitting. It is also possible that you are even obligated to say the berachah Leisheiv basukkah under these circumstances. (Mishnah Berurah 639:33) How heavy a rain must it be for you to be exempt? If it rains so much, that in your judgment, if that much rain would drip into your cooked food,11This is true even if the food is of the kind that spoils quickly because of a little water. (Mishnah Berurah 639:34) it would be spoiled, even if the food is not actually in the sukkah, or if you estimate,12If you are unable to make such a judgment, you should use the next example quoted in the text as a criterion. (Ramah 639:5) that if it would rain that much into the room where you are sitting, you would move into another room, then you may leave the sukkah and go into the house. If you started to eat in the sukkah, and then it began to rain, so that you went into the house and started to eat there; or because of the rain you began initially to eat in the house, and then it stopped raining, you may finish your meal in the house, and you are not obligated to leave while the meal is in progress, to go from your house into the sukkah. When it is so cold that the food in the sukkah jells,13This is certainly true if you are troubled because of the cold. (Shaar Hatzion 639:59) you are exempt from sitting in the sukkah, and you may eat in the house.14This halachah also holds true if the climate is so intensely hot or if there are many insects that cause you to be uncomfortable, or will cause the food to become inedible. (Mishnah Berurah 639:31)
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.)