It is written, "And you must guard the matzos" (Exodus 12:17). From this we learn that we must guard the wheat [from which we make] the matzos with which we perform the mitzvah, to see that no water comes upon them. According to some of the great halachic authorities, of blessed memory, this watchfulness is to begin from the time the wheat is harvested. The prevailing custom is to follow the opinion of the authorities, who maintain it is sufficient to guard it from the time it is brought to the mill, and thereafter. However, people who are meticulous in their performance of mitzvos, are concerned that [the wheat] should be guarded from the time it is harvested, and this is the proper thing to do. Special care must be taken that the stalks do not remain attached to the earth until they completely dry out and turn white, because then if rain falls on them they will become chametz, even though they are still attached to the soil,1 since they no longer need the soil's (nourishment). It is, therefore, fitting and proper to harvest them when they are still slightly green. If you can obtain wheat that was guarded from the time of harvesting for all the days of Yom Tov, so much the better. If this is impossible, you should at least be scrupulous about this for the matzos of both Seder nights.


כְּתִיב וּשְׁמַרְתֶּם אֶת הַמַּצּוֹת, מִכָּאן, שֶׁצְּרִיכִין לִשְׁמוֹר אֶת הַחִטִּין לְשֵׁם מַצּוֹת מִצְוָה, שֶׁלֹּא יָבוֹאוּ עֲלֵיהֶם מַיִם. וּלְדַעַת קְצָת מִגְּדוֹלֵי הַפּוֹסְקִים זִכְרוֹנָם לִבְרָכָה, צְרִיכִין שְׁמִירָה זוֹ מִיָּד מִשְּׁעַת קְצִירָה וָאֵילָךְ. אֲבָל הַמִּנְהָג הוּא כְּהַפּוֹסְקִים דְּסַגֵּי לְהוּ בִּשְׁמִירָה מִשָּׁעָה שֶׁמּוֹלִיכִין אוֹתָן לִטְחוֹן וָאֵילֶךְ. וְאַךְ הַמְדַקְדְּקִין בַּמִצְווֹת, חוֹשְׁשִׁין לִשְׁמִירָה מִשְּׁעַת קְצִירָה, וְכֵן נָכוֹן לַעֲשׂוֹת. וְרָאוּי לְדַקְדֵּק שֶׁלֹּא יַעַמְדוּ הַשִּׁבָּלִים בִּמְחֻבָּר עַד שֶׁיִּתְיַבְּשׁוּ כָּל צָרְכָּן וְיַלְבִּינוּ, כִּי אָז אִם יֵרְדוּ עֲלֵיהֶן גְּשָׁמִים, יַחְמִיצוּ אֲפִלּוּ בִּמְחֻבָּר, כֵּיוָן שֶׁאֵינָן צְרִיכוֹת עוֹד לַקַּרְקַע. עַל כֵּן רָאוּי וְנָכוֹן לִקְצוֹר בְּעוֹד שֶׁיֶשׁ בָּהֶן עוֹד קְצָת מַרְאֵה יַרְקוּת. וּמִי שֶׁאֶפְשָׁר לוֹ בְּחִטִּין שְׁמוּרוֹת מִשְּׁעַת קְצִירָה לְכָל יְמֵי הָחָג, מַה טּוֹב. וְאִם לָאו, רָאוּי לוֹ עַל כָּל פָּנִים לְהַדֵּר בָּזֶה לַמַּצּוֹת שֶׁעַל הַסֵּדֶר בִּשְׁנֵי הַלֵּילוֹת (עַיֵן חַיֵּי אָדָם כְּלָל קכ"ח סִימָן ל').


If in some of the wheat there was found kernels that were split open or sprouted; the rest may be used for matzah, provided the unfit ones were separated or carefully measured to make sure that there is at least sixty times as much (of the good wheat) as the split and sprouted (wheat). Initially, you should be scrupulous to sort out even wheat from which mice have eaten, or to make sure that there is at least sixty times as much of the good wheat. Wheat that arrived by ship or was stored in pits, if it is dry and hard, and its color has not changed, is kosher for Pesach. If it was stored in an attic and rain dripped upon it in several places, through the roof, it is forbidden. But if a little snow fell on it or a little water, in one place only, you must remove those kernels which are doubtful, and the rest may be used.


חִטִּים שֶׁנִּמְצְאוּ בָהֶן מְבֻקָּעוֹת אוֹ מְצֻמָּחוֹת, הַשְּׁאָר מֻתָּר. וּבִלְבַד שֶׁיִּבְרְרוּ אוֹתָן, אוֹ צְרִיכִין לְדַקְדֵק הֵיטֵב, אִם יֵשׁ שָׁם עַל כָּל פָּנִים שִׁשִּׁים כְּנֶגֶד הַמְבֻקָּעוֹת וְהַמְצֻמָּחוֹת. וּלְכַתְּחִלָּה יֵשׁ לְהַדֵּר לִבְרֹר גַּם מִן הַחִטִּים שֶׁאָכְלוּ מֵהֶן עַכְבָּרִים אוֹ שֶׁיִּהְיֶה שִׁשִּׁים כְּנֶגְדָּן. וְהַחִטִּים שֶׁבָּאוּ בַּסְּפִינָה אוֹ שֶׁהָיוּ מֻנָּחוֹת בַּבּוֹרוֹת, אִם הֵן יְבֵשׁוֹת וְקָשׁוֹת וְלֹא נִשְׁתַּנָּה מַרְאֵיהֶן, כְּשֵׁרוֹת. וְאִם הָיוּ מֻנָּחוֹת בַּעֲלִיָּה וְיָרְדוּ עֲלֵיהֶן גְּשָׁמִים דֶּרֶךְ הַגַּג בִּקְצָת מְקוֹמוֹת, אֲסוּרוֹת. אֲבָל אִם נָפַל עֲלֵיהֶן קְצָת שֶׁלֶג אוֹ קְצָת מַיִם בְּמָקוֹם אֶחָד, מְסַלֵּק אוֹתָן שֶׁיֵּשׁ לְהִסְתַּפֵּק בָּהֶן. וְהַשְּׁאָר מֻתָּרוֹת (תנ"ג תס"ז).


It is a long established custom in Yisroel, in preparing the mill, to clean it thoroughly, and scrub it in every possible way and to purchase new bags [for the flour.] In a community where there are Torah scholars, they should go to the mill to supervise the cleansing, and to see that the preparations are done properly. In a community where there are no Torah scholars, every God-fearing person should go himself to supervise the preparation of the mill, for it is a greater mitzvah to do it yourself, than if an agent does it for you. It is customary that the first flour milled after this preparation, is not eaten on Pesach. If moist grain is also ground at that mill, it should be separated with a partition, so that none of its powder should mix with it.


כְּבָר נָהֲגוּ יִשְֹרָאֵל לְדַקְדֵק בְּהֶכְשֵׁר הָרֵיחַיִם, לְנַקֵּר הֵיטֵב וּלְנַקּוֹת בְּכָל הָאֶפְשָׁרִי. וְכִיסִים לוֹקְחִים חֲדָשִׁים וּבְמָקוֹם שֶׁיֵּשׁ תַּלְמִידֵי חֲכָמִים הֵמָּה הוֹלְכִים אֶל הָרֵיחַיִם לְהַשְׁגִּיחַ שֶׁיְהֵא הַהֶכְשֵׁר כָּרָאוּי, וּבְמָקוֹם שֶׁאֵין תַּלְמִידֵי חֲכָמִים רָאוי לְכָל יְרֵא שָׁמַיִם שֶׁיֵּלֵךְ בְּעַצְמוֹ לְהַשְׁגִּיחַ עַל הַהֶכְשֵׁר דְּמִצְוָה בּוֹ יוֹתֵר מִבִּשְׁלוֹחוֹ, וְנוֹהֲגִין שֶׁהַקֶּמַח הָרִאשׁוֹן שֶׁנִּטְחַן לְאַחַר הַהֶכְשֵׁר אֵין אוֹכְלִין אוֹתוֹ בְּפֶסַח, אִם טוֹחֲנִין בָּרֵיחַיִם גַּם תְּבוּאָה לְתוּתָה, צְרִיכִין לְהַפְסִיק בִּמְחִצָּה, שֶׁלֹּא יִתְעָרֵב בּוֹ מִן הָאָבָק הַהוּא (תנ"ג).


If a bag of flour has become wet, if only one part became wet, whether it is still moist or already dry, you may take that part in your hand while you empty the rest of the flour, which you are permitted to use. Only the part that has become wet is forbidden. However, if the bag of flour has become wet in several places so that it is impossible to take these steps, then, if it is still moist, the flour is sifted and only the pieces that remain in the sieve are chametz, but the rest may be used. If mice have eaten some of the flour, it should be sifted. However, if the bag of flour has become dry, sifting is of no use, and the entire flour is forbidden to be used.


שַׂק עִם קֶמַח שֶׁנִּתְלַחְלַח מִמַּיִם, אִם הוּא בְּמָקוֹם אֶחָד, בֵּין שֶׁהוּא עֲדַיִן לַח בֵּין שֶׁנִּתְיַבֵּשׁ, יֹאחֵז אֶת הַמָּקוֹם הַזֶּה בְּיָדוֹ וְיָרִיק הַשְּׁאָר, וּמֻתָּר. רַק זֶה שֶׁנִּתְלַחְלַח, אָסוּר. וְאִם נִתְלַחְלַח בְּכַמָּה מְקוֹמוֹת שֶׁאִי אֶפְשָׁר לוֹ לַעֲשׂוֹת כֵּן, אֲזַי אִם עֲדַיִן הוּא לַח, יְרַקֵד אֶת הַקֶּמַח. וּמַה שֶׁנִּשְׁאַר עַל הַנָּפָּה פֵּרוּרִין, זֶהוּ לְבַד חָמֵץ וְהַשְּׁאָר מֻתָּר. וְכֵן אִם אָכְלוּ עַכְבָּרִים מִן הַקֶּמַח, יְרַקְּדֶנוּ. אֲבָל אִם כְּבָר נִתְיַבֵּשׁ, לֹא מַהֲנֵי לֵה הַרְקָדָה וְכָל הַקֶּמַח אָסוּר (תס"ו).


On the day the flour has been ground it is forbidden to be baked,2 because the flour is then warm and will quickly become chametz when water is poured on it. Therefore, you should postpone using it for at least twenty-four hours after the grinding.


בַּיּוֹם שֶׁטָּחֲנוּ אֶת הַקֶּמַח, אָסוּר לֶאֱפוֹתוֹ, מִפְּנֵי שֶׁאָז הַקֶּמַח הוּא חַם וּמְמַהֵר לְהַחְמִיץ כְּשֶׁנּוֹתְנִים בּוֹ אֶת הַמַּיִם, עַל כֵּן יִשְׁהֶה אַחַר הַטְּחִינָה לְכָל הַפָּחוֹת מֵעֵת לְעֵת.


The bags for holding the flour preferably should be made new, or at least the seams of the old bags should be opened, and they should be washed thoroughly with warm water and ashes, and by rubbing and beating them.


הַשַּׂקִּים שֶׁמַּנִּיחִים בָּהֶם אֶת הַקֶּמַח, טוֹב לַעֲשׂוֹתָן חֲדָשִׁים, אוֹ לְכָל הַפָּחוֹת לְהַתִּיר אֶת הַתְּפִירוֹת וּלְכַבֵּס הֵיטֵב הֵיטֵב בְּחַמִּין וּבְאֵפֶר וּבְשִׁפְשׁוּף וַחֲבִיטָה.


It is forbidden to load a bag of flour on an animal, unless thick leather is placed underneath the bag, as otherwise, it will get warm and moist from perspiration. If possible, you should also be careful not to place many bags one on top of the other, because as a result of that, the flour will be heated, and become chametz in the kneading.3


אָסוּר לְהַנִּיחַ שַׂק עִם קֶמַח עַל גַּבֵּי בְּהֵמָה, אֶלָּא אִם יֵשׁ עוֹר עָבֶה תַּחְתָּיו, דְּאִם לֹא כֵּן יִתְחַמֵּם וְיִתְלַחְלֵח מִן הַזֵּעָה. וְאִם אֶפְשָׁר, יִזָּהֵר גַּם כֵּן שֶׁלֹּא לְהַנִּיחַ הַרְבֵּה שַׂקִּים זֶה עַל זֶה, מִפְּנֵי שֶׁעַל יְדֵי זֶה מִתְחַמֵּם וְיַחְמִיץ בַּלִּישָׁה.