שֶׁלֹּא לַחְסֹם בְּהֵמָה בִּשְׁעַת מְלַאכְתָּהּ – שֶׁלֹּא נִמְנַע הַבְּהֵמָה מִלֶּאֱכֹל מִמָּה שֶׁתַּעֲבֹד בּוֹ בִּשְׁעַת עֲבוֹדָה, כְּגוֹן שֶׁתָּדוּשׁ תְּבוּאָה אוֹ תִּשָּׂא תֶּבֶן מִמָּקוֹם לְמָקוֹם עַל גַּבָּהּ, שֶׁאֵין רְשׁוּת לָנוּ לְמָנְעָהּ מִלֶּאֱכוֹל מִמֶּנָּה, וְעַל זֶה נֶאֱמַר (דברים כה ד) לֹא תַחְסֹם שׁוֹר בְּדִישׁוֹ. To not muzzle an animal at the time of its work: To not prevent an animal from eating that which it is working on, at the time of its work — for example, when it threshes grain or carries straw from place to place on its back — as we do not have permission to prevent it from eating from it. And about this is it stated (Deuteronomy 25:4), “You shall not muzzle an ox in its threshing.”
מִשָּׁרְשֵׁי הַמִּצְוָה. לְלַמֵּד עַצְמֵנוּ לִהְיוֹת נַפְשֵׁנוּ נֶפֶשׁ יָפָה בּוֹחֶרֶת הַיֹּשֶׁר וּמִדַּבֶּקֶת בּוֹ וְרוֹדֶפֶת אַחַר הַחֶסֶד וְהַחֶמְלָה, וּבְהַרְגִּילֵנוּ אוֹתָהּ עַל זֶה אַף עַל הַבְּהֵמוֹת שֶׁלֹּא נִבְרְאוּ רַק לְשַׁמְּשֵׁנוּ, לָחוּס עֲלֵיהֶן לְחַלֵּק לָהֶן חֵלֶק מִיְּגִיעַת בְּשָׂרָן, תִּקַּח לָהּ הַנֶּפֶשׁ דַּרְכָּהּ בְּהֶרְגֵּל זֶה, לְהֵטִיב אֶל בְּנֵי אָדָם וְלִשְׁמוֹר אוֹתָם מֵהַעֲבִיר עֲלֵיהֶם הַדֶּרֶךְ בְּשׁוּם דָּבָר שֶׁרָאוּי לָהֶם, וּלְשַׁלֵּם שְׂכָרָם כְּכָל אֲשֶׁר יַעֲשׂוּ טוֹב, וּלְהַשְׂבִּיעָם מֵאֲשֶׁר יִיגְעוּ בּוֹ. וְזֶה הַדֶּרֶךְ רָאוּי יֵלְכוּ בָּהּ עַם הַקֹּדֶשׁ הַנִּבְחָר. It is from the roots of the commandment [that it is] to teach ourselves that our souls be a good soul that chooses what is right and clings to it and pursues kindness and mercy. And in our accustoming it to this — even with animals that were only created to serve us, to be concerned for them to distribute to them a portion of the toil of their flesh — the soul will take for itself the way of this habit; to do good to people and to guard from taking access away from them for anything that is appropriate for them, and to repay their reward according to all the good that they do and to satiate them with that upon which they toiled. And it is fitting for the holy chosen nation to follow this way.
מִדִּינֵי הַמִּצְוָה. מָה שֶׁאָמְרוּ זִכְרוֹנָם לִבְרָכָה (ב"מ פט, א רמב"ם שכירות פי"ג הל' א ב) שֶׁאִסּוּר חֲסִימָה הוּא כְּשֶׁעוֹשָׂה הַבְּהֵמָה בְּגִדּוּלֵי הַקַּרְקַע, בֵּין בִּמְחֻבָּר בֵּין בְּתָלוּשׁ. וְאֶחָד הַשּׁוֹר וְאֶחָד כָּל מִינֵי בְּהֵמָה וְחַיָּה, בֵּין טְמֵאִים בֵּין טְהוֹרִים בִּכְלַל אִסּוּר זֶה. וְאֶחָד הַדָּשׁ וְאֶחָד כָּל שְׁאָר מִינֵי מְלָאכוֹת שֶׁל גִּדּוּלֵי קַרְקַע, וְלֹא נֶאֱמַר שׁוֹר בְּדִישׁוֹ אֶלָּא בַּהֹוֶה. וְהַחוֹסֵם אֶת הַפּוֹעֵל פָּטוּר. וְאֶחָד הַחוֹסֵם אוֹתָהּ בִּשְׁעַת מְלָאכָה אוֹ קֹדֶם מְלָאכָה וְאַחַר כָּךְ עָשָׂה בָּהּ מְלָאכָה חַיָּב מִשּׁוּם חֲסִימָה. וְדִין הַדָּשׁ בְּפָרָתוֹ שֶׁל גּוֹי (שם צ, א), וְהָאוֹמֵר לְגוֹי חֲסֹם פָּרָתִי וְדוּשׁ בָּהּ, וְדִין אִם הָיָה רַע לִבְנֵי מֵעֶיהָ מָה שֶׁהוּא עוֹשֶׂה בּוֹ, וְדִין פָּרוֹת הַמְּהַלְּכוֹת עַל הַתְּבוּאָה (שם פט, ב), וְיֶתֶר פְּרָטֶיהָ, מְבֹאָרִין בְּפֶרֶק שְׁבִיעִי מִבָּבָא מְצִיעָא [ח"ה סי' שלח]. From the laws of the commandment is that which they, may their memory be blessed, said (Bava Metzia 89a, see Mishneh Torah, Hiring 13:1-2) that the prohibition of muzzling is when the animal is involved with that which grows from the ground, whether it is attached or removed. And it is one whether it is an ox or it is any type of beast or animal, whether they are impure or pure — they are all included in this prohibition. And it is one whether it is threshing or it is [involved] in any type of work with that which grows from the ground. And “ox in its threshing” is only stated because it is common. And one who muzzles a worker is exempt. And it is one whether one muzzles [an animal] during the time of the work or before the work and it does the work afterwards — he is guilty for muzzling. And the law of threshing with the cow of a gentile (Bava Metzia 90a), and one who says to a gentile, “Muzzle my cow and thresh with it”; the law if what it is working with is bad for its intestines; the law of a cow that is walking on grain (Bava Metzia 89b); and the rest of its details are elucidated in the seventh chapter of Bava Metzia. (See Tur, Choshen Mishpat 338.)
וְנוֹהֵג אִסּוּר זֶה בְּכָל מָקוֹם וּבְכָל זְמַן, בִּזְכָרִים וּנְקֵבוֹת. וְהָעוֹבֵר (שם צ, ב) עַל זֶה וְחָסַם פָּרָתוֹ וְדָשׁ בָּהּ, חַיָּב מַלְקוּת. וַאֲפִלּוּ חֲסָמָהּ בְּקוֹל לוֹקֶה, כְּגוֹן שֶׁמּוֹנֵעַ הַפָּרָה מִלֶּאֱכוֹל בְּקוֹל גַּעֲרוֹתָיו, שֶׁעֲקִימַת שְׂפָתָיו בָּזֶה הוּא חָשׁוּב מַעֲשֶׂה גָּדוֹל לְהַלְקוֹתוֹ עָלָיו, כַּנִּרְאֶה בְּסַנְהֶדְרִין (סה ב). (וְתֵמַהּ הוּא מַאי שְׁנָא הָכָא מִשְּׁאָר דּוּכְתֵּי דְּאֵין לוֹקִין עַל לָאו דְּאֵין בּוֹ מַעֲשֶׂה). וְהַשּׂוֹכֵר בְּהֵמָה וַחֲסָמָהּ לוֹקֶה וּמְשַׁלֵּם לַבְּעָלִים אַרְבַּעַת קַבִּין לַפָּרָה, וּשְׁלֹשֶׁת קַבִּין לַחֲמוֹר. And this prohibition is practiced in every place and at all times by males and females. And one who transgresses it and muzzles his cow and threshes with it is liable for lashes (Bava Metzia 90b). And even if he muzzled it with [his] voice, he is lashed — for example, [if] he prevents the cow from eating with the call of his rebukes. As the twisting of the lips in this is considered a major act, to give him lashes for it, as is apparent from Sanhedrin 65b. (And it is a wonder: what is different here from other places where we do not lash for a negative commandment that has no [true] act.) And one who rents an animal and muzzles it is lashed and repays the owners — four kav for a cow and three kav for a donkey.