אורח חיים תל״טOrach Chayim 439

Se’if 1א׳

ט' צִבּוּרִין שֶׁל מַצָּה וְאֶחָד שֶׁל חָמֵץ, וּבָא עַכְבָּר וְנָטַל וְלֹא יָדַעְנוּ אִם נָטַל חָמֵץ אוֹ אִם נָטַל מַצָּה, וְנִכְנַס לְבַיִת בָּדוּק, צָרִיךְ לַחֲזֹר וּלְבָדְקוֹ, מִיהוּ אִם הַכִּכָּר קָטָן שֶׁיָּכוֹל הָעַכְבָּר לֶאֱכֹל תָּלִינָן לְהָקֵל שֶׁאֲכָלוֹ וְאֵין צָרִיךְ לִבְדֹּק (טוּר), שֶׁכָּל הַקָּבוּעַ כְּמֶחֱצָה עַל מֶחֱצָה; וְאִם פֵּרֵשׁ הַכִּכָּר מִמְּקוֹם קְבִיעָתוֹ, וּנְטָלוֹ הָעַכְבָּר מִשָּׁם, אֵין צָרִיךְ לַחֲזֹר וְלִבְדֹּק; דְּכָל דְּפָרִישׁ, מֵרֻבָּא פָּרִישׁ.

The Law Concerning One Who Checked and Did Not Find the Number of Loaves He Had Left. Containing 4 Paragraphs: Nine piles of matza, and one of chametz, and a mouse comes and takes [from the piles] and we do not know if the mouse took chametz or matza, and the mouse entered a checked house - you must return and check it (however, if the food is small enough that the mouse could have eaten it - we can rely on a leniency that the mouse did eat it, and you do not need to check) (Tur), as every established place is like a half of a half [i.e. each established location is treated as its own majority]. If the food was separated from its established place, and the mouse took it from there - you do not need to return and check it, as anything separated [is considered to be] separated from the majority.

Se’if 2ב׳

ב' צִבּוּרִין, אֶחָד שֶׁל חָמֵץ וְאֶחָד שֶׁל מַצָּה, וּב' בָּתִּים, אֶחָד בָּדוּק וְאֶחָד שֶׁאֵינוֹ בָּדוּק, וּבָאוּ שְׁנֵי עַכְבָּרִים זֶה נָטַל חָמֵץ וְזֶה נָטַל מַצָּה וְאֵין יָדוּעַ לְאֵיזֶה בַּיִת נִכְנַס זֶה שֶׁנָּטַל הֶחָמֵץ; וְכֵן שְׁנֵי בָּתִּים בְּדוּקִים וְצִבּוּר אֶחָד שֶׁל חָמֵץ וּבָא עַכְבָּר וְנָטַל וְאֵין יָדוּעַ לְאֵיזֶה בַּיִת נִכְנַס, אוֹ שֶׁיָּדַע שֶׁנִּכְנַס לְאֶחָד מֵהֶם וְנִכְנַס אַחֲרָיו וּבָדַק וְלֹא מָצָא כְּלוּם, אוֹ שֶׁבָּדַק קְצָת מֵהַבַּיִת וּמָצָא כִּכָּר, אֵינוֹ צָרִיךְ לַחֲזֹר וְלִבְדֹּק. כָּךְ הֵם דִּבְרֵי הַרַמְבַּ"ם, אֲבָל מַסְקָנַת הַפּוֹסְקִים אֵינוֹ כֵּן.

If there are two piles, one of chametz and one of matzah, and two houses, one that was checked and one that was not, and two mice came — one took chametz, and one took matzah — and we do not know which mouse entered which house: Or if both houses were checked and there was one pile of chametz, and a mouse came and took from it, and it is not known into which house it entered; Or even if we know it entered one of them, and someone entered after it and checked and found nothing, Or he checked part of the house and found a loaf, In all these cases, there is no need to recheck the house. (These are the words of the Rambam, but the conclusion of later halakhic authorities is not in agreement with him.)

Se’if 3ג׳

הִנִּיחַ ט' כִּכְּרוֹת חָמֵץ וּמָצָא י', צָרִיךְ לִבְדֹּק אַחַר כָּל הַט'. וְכֵן אִם הִנִּיחַ י' וּמָצָא ט', צָרִיךְ לִבְדֹּק אַחַר כָּל הַי' שֶׁאָנוּ אוֹמְרִים מַה שֶּׁהִנִּיחַ נָטַל וְאֵלּוּ אֲחֵרִים הֵם. וְיֵשׁ אוֹמְרִים דְּהָנֵי מִלֵּי בִּקְשׁוּרִים יַחַד, אֲבָל אִם אֵינָם קְשׁוּרִים יַחַד אֵין צָרִיךְ לִבְדֹּק אֶלָּא אַחַר הָאֶחָד.

If one left nine loaves of chametz and found ten, he must check for all nine, because we say that what he left was taken, and these are others (i.e., new ones). Similarly, if he left ten and found nine, he must check for all ten. But some say this only applies when the loaves were tied together, but if they were not tied, he only needs to check for the one that is missing or added.