To not do work with two species of animals: To not plow with an ox and a donkey together. And the same is the case with any two species of animals, when one is pure and the other one is impure. And it is not specifically plowing that is forbidden, but rather the same is true for all types of work — for example, threshing or pulling a wagon [or] any of the types of work. And about this is it stated (Deuteronomy 22:10), “You shall not plow with an ox and a donkey together.”
[Concerning] the root of the commandment, Rambam, may his memory be blessed, wrote (Guide for the Perplexed 3:49, see also Ramban on Deuteronomy 22:10) that it is from the root of the prohibition of interbreeding animals as a forbidden mixture. As the way of workers of the land is to bring a pair (of animals) from one barn and lest [and there] he would graft them. And the root of the prohibition of interbreeding I wrote in its place in the Order of Kedoshim Tehiyu (Sefer HaChinukh 244). And after permission of the Master — the teacher mentioned — and concession to his good word, I will also answer my portion. And I say that from the explanations of this commandment is the matter of [causing] pain to animals, which is a prohibition of the Torah. And it is known that for species of animals and fowl, there is great anguish in dwelling with those that are not its species and — all the more so — to do work with them. And [it is] as we see with our eyes with the ones that are not under our hands (undomesticated species) that every bird dwells with its species; and all animals and other species also always cling to their [own] species. And any wise-hearted person will [learn] proper conduct from this, to never put together two people whose natures are different from one another and different in their behavior in any matter — like a righteous person and an evildoer [or] a slight person and an honorable one. Since if the Torah was exacting about the pain that there is to animals — that are not intelligent creatures — from this, all the more so [is this the case] with people that have an intelligent soul, in order to know their Maker.
From the laws of the commandment is that which they, may their memory be blessed, said (see Sefer HaMitzvot, Negative Commandments 218 and Mishneh Torah, Diverse Species 9:7) that the obligation of this commandment from Torah writ is only with two species like the ox and the donkey — that one of them is pure and the second one impure, [such] that their natures are very distant from one another. But with two species that are [both] pure or impure — like an ox and a goat, or a donkey and horse — it is not forbidden from the Torah. Rather it is [only] rabbinically that any two species that would [constitute a case of] forbidden interbreeding are forbidden — and both [domesticated] beasts and [undomesticated] animals are included in the prohibition. And it is the same whether one plows with them or seeds or pulls a wagon with them. And so [too,] if one [person] was sitting in the wagon and one was leading [them] — both of them are lashed, because his sitting in the wagon [also] causes the animal to pull. (See Mishneh Torah, Diverse Species 9:9.) And even if a hundred [people] led together, all of them are lashed. And [about] that which they said that it is permissible to do all work with a person and an animal, as it states, “with an ox and a donkey” — and not with a person and a donkey or a person and an ox (see Mishneh Torah, Diverse Species 9:10) — the explanation of the matter is according to the root that we mentioned. As the joining of an animal is not distressing for a person, since there is no connection with it at all. And behold, it is like he is doing work with a tree or a stone; and [so] it does not at all come into the designation that we spoke about. And also from the matter of the commandment is that which Rabbi Yitschak said at the end of Makkot 22a, that one who leads an ox of those disqualified from the consecrated is lashed — even though it is one body, the verse made it like two bodies to be lashed for. And the rest of its details are explained in the eighth chapter of Kilayim. (See Tur, Yoreh Deah 297.)
And this prohibition is practiced in every place and at all times by males and females. And one who transgresses this and seeds or plows or pulls or leads with a forbidden mixture — which are two species, one impure and one pure — is liable for lashes from Torah writ. And he is liable for lashes even if he led them together with his voice alone — like the way of animals that sometimes walk with the coaxing of people, as it is stated, “together” — in any case. They, may their memory be blessed, made a precise inference from the words of the verse to obligate lashes [even] with speech without a deed. And in [the case of] two species that were [both] impure or pure, that are forbidden to interbreeding with each other, he is rabbinically liable for lashes of rebellion.
שֶׁלֹּא לַעֲשׂוֹת מְלָאכָה בִּשְׁנֵי מִינֵי בְּהֵמוֹת – שֶׁלֹּא לַחֲרֹשׁ בְּשׁוֹר וּבַחֲמוֹר יַחְדָּו, וְהוּא הַדִּין לְכָל שְׁנֵי מִינֵי בְּהֵמָה שֶׁהָאַחַת הִיא טְהוֹרָה וְהָאַחַת הִיא טְמֵאָה. וְלָאו דַּוְקָא חֲרִישָׁה לְבַד אֲסוּרָה, אֶלָּא הוּא הַדִּין לְכָל מְלָאכָה מֵהַמְּלָאכוֹת, כְּגוֹן דִּישָׁה אוֹ לִמְשֹׁךְ עֲגָלָה וְכָל שְׁאָר מְלָאכוֹת, וְעַל זֶה נֶאֱמַר (דברים כב י) לֹא תַחֲרֹשׁ בְּשׁוֹר וּבַחֲמֹר יַחְדָּו.
To not do work with two species of animals: To not plow with an ox and a donkey together. And the same is the case with any two species of animals, when one is pure and the other one is impure. And it is not specifically plowing that is forbidden, but rather the same is true for all types of work — for example, threshing or pulling a wagon [or] any of the types of work. And about this is it stated (Deuteronomy 22:10), “You shall not plow with an ox and a donkey together.”
שֹׁרֶשׁ הַמִּצְוָה. כָּתַב הָרַמְבַּ"ם זִכְרוֹנוֹ לִבְרָכָה (מורה נבוכים ח"ג פרק מ"ט, והרמב"ן בפי' לחומש) שֶׁהוּא מִשֹּׁרֶשׁ אִסּוּר הַרְבָּעַת הַבְּהֵמָה כִּלְאַיִם, כִּי דֶּרֶךְ עוֹבְדֵי אֲדָמָה לְהָבִיא הַצֶּמֶד בְּרֶפֶת אַחַת וְשֶׁמָּא [וְשָׁמָּה] יַרְכִּיב אוֹתָם, וְשֹׁרֶשׁ אִסּוּר הַרְבָּעָה כְּתַבְתִּיו בִּמְקוֹמוֹ בְּסֵדֶר קְדוֹשִׁים תִּהְיוּ (מצוה רמד). וְאַחַר רְשׁוּת אֲדוֹנִי הָרַב הַנִּזְכָּר וְהוֹדָאָה עַל דְּבָרוֹ הַטּוֹב אַעֲנֶה אַף אֲנִי חֶלְקִי, וְאוֹמַר כִּי מִטַּעְמֵי מִצְוָה זוֹ, עִנְיַן צַעַר בַּעֲלֵי חַיִּים שֶׁהוּא אָסוּר מִן הַתּוֹרָה, וְיָדוּעַ שֶׁיֵּשׁ לְמִינֵי הַבְּהֵמוֹת וְלָעוֹפוֹת דְּאָגָה גְּדוֹלָה לִשְׁכֹּן עִם שֶׁאֵינָם מִינָן וְכָל שֶׁכֵּן לַעֲשׂוֹת עִמָּהֶן מְלָאכָה, וּכְמוֹ שֶׁאָנוּ רוֹאִים בְּעֵינֵינוּ בְּאוֹתָם שֶׁאֵינָם תַּחַת יָדֵינוּ, כִּי כָּל עוֹף לְמִינוֹ יִשְׁכֹּן, וְכָל הַבְּהֵמוֹת וּשְׁאָר הַמִּינִין גַּם כֵּן יִדְבְּקוּ לְעוֹלָם בְּמִינֵיהֶן, וְכָל חֲכַם לֵב מִזֶּה יִקַּח מוּסָר שֶׁלֹּא לְמַנּוֹת שְׁנֵי אֲנָשִׁים לְעוֹלָם בְּדָבָר מִכָּל הַדְּבָרִים שֶׁיִּהְיוּ רְחוֹקִים בְּטִבְעָם וּמְשֻׁנִּים בְּהַנְהָגָתָם, כְּמוֹ צַדִּיק וְרָשָׁע, וְהַנִּקְלֶה בַּנִּכְבָּד, שֶׁאִם הִקְפִּידָה הַתּוֹרָה עַל הַצַּעַר שֶׁיֵּשׁ בָּזֶה לְבַעֲלֵי חַיִּים שֶׁאֵינָם בְּנֵי שֵׂכֶל, כָּל שֶׁכֵּן בִּבְנֵי אָדָם אֲשֶׁר לָהֶם נֶפֶשׁ מַשְׂכֶּלֶת לָדַעַת יוֹצְרָם.
[Concerning] the root of the commandment, Rambam, may his memory be blessed, wrote (Guide for the Perplexed 3:49, see also Ramban on Deuteronomy 22:10) that it is from the root of the prohibition of interbreeding animals as a forbidden mixture. As the way of workers of the land is to bring a pair (of animals) from one barn and lest [and there] he would graft them. And the root of the prohibition of interbreeding I wrote in its place in the Order of Kedoshim Tehiyu (Sefer HaChinukh 244). And after permission of the Master — the teacher mentioned — and concession to his good word, I will also answer my portion. And I say that from the explanations of this commandment is the matter of [causing] pain to animals, which is a prohibition of the Torah. And it is known that for species of animals and fowl, there is great anguish in dwelling with those that are not its species and — all the more so — to do work with them. And [it is] as we see with our eyes with the ones that are not under our hands (undomesticated species) that every bird dwells with its species; and all animals and other species also always cling to their [own] species. And any wise-hearted person will [learn] proper conduct from this, to never put together two people whose natures are different from one another and different in their behavior in any matter — like a righteous person and an evildoer [or] a slight person and an honorable one. Since if the Torah was exacting about the pain that there is to animals — that are not intelligent creatures — from this, all the more so [is this the case] with people that have an intelligent soul, in order to know their Maker.
מִדִּינֵי הַמִּצְוָה. מָה שֶׁאָמְרוּ זִכְרוֹנָם לִבְרָכָה (רמב"ם ספהמ"צ ל"ת ריח ובהל' כלאים פ"ט ה"ז) שֶׁאֵין חִיּוּב מִצְוָה זוֹ מִן הַתּוֹרָה כִּי אִם בִּשְׁנֵי מִינִין שֶׁהֵם כְּגוֹן שׁוֹר וַחֲמוֹר, שֶׁהָאֶחָד טָהוֹר וְהַשֵּׁנִי טָמֵא, שֶׁטִּבְעָם רָחוֹק מְאֹד זֶה מִזֶּה, אֲבָל בִּשְׁנֵי מִינִין טְהוֹרִים אוֹ טְמֵאִים, אַף עַל פִּי שֶׁאֵינָם מִין אֶחָד, כְּגוֹן שׁוֹר וְתַיִשׁ אוֹ חֲמוֹר וְסוּס אֵינוֹ אָסוּר מִן הַתּוֹרָה, אֲבָל מִדְּרַבָּנָן הוּא שֶׁאָסוּר בְּכָל שְׁנֵי מִינִים שֶׁהֵם כִּלְאַיִם בְּהַרְבָּעָה, וְאֶחָד בְּהֵמָה אוֹ חַיָּה בִּכְלַל הָאִסּוּר. וְאֶחָד הַחוֹרֵשׁ בָּהֶן אוֹ זוֹרֵעַ אוֹ מוֹשֵׁךְ בָּהֶן עֲגָלָה, וְכֵן (רמב"ם שם ט) אִם הָיָה אֶחָד יוֹשֵׁב בָּעֲגָלָה וְאֶחָד מַנְהִיג שְׁנֵיהֶן לוֹקִין, מִפְּנֵי שֶׁיְּשִׁיבָתוֹ בָּעֲגָלָה גּוֹרֶמֶת לַבְּהֵמָה שֶׁתִּמָּשֵׁךְ. וַאֲפִלּוּ מֵאָה שֶׁהִנְהִיגוּ כְּאֶחָד כֻּלָּם לוֹקִין. וּמָה שֶׁאָמְרוּ (רמב"ם שם ה"י) שֶׁמֻּתָּר לַעֲשׂוֹת כָּל מְלָאכָה בְּאָדָם וּבְהֵמָה, שֶׁנֶּאֱמַר בְּשׁוֹר וּבַחֲמוֹר, וְלֹא בְּאָדָם וַחֲמוֹר אוֹ בְּאָדָם וְשׁוֹר, וְטַעַם הָעִנְיָן לְפִי הַשֹּׁרֶשׁ שֶׁאָמַרְנוּ, מִפְּנֵי שֶׁאֵין הִתְחַבְּרוּת הַבְּהֵמָה צַעַר לָאָדָם, כִּי אֵין לוֹ עִמָּהּ חֶבְרָה כְּלָל, וַהֲרֵי הוּא כָּעוֹשֶׂה מְלָאכָה אֵצֶל עֵץ אֶחָד אוֹ אֶבֶן אַחַת, וְאֵינוֹ בָּא כְּלָל בְּגֶדֶר הַדָּבָר שֶׁדִּבַּרְנוּ עָלָיו. וְכֵן מֵעִנְיַן הַמִּצְוָה, מָה שֶׁאָמַר רַבִּי יִצְחָק בְּסוֹף מַכּוֹת (כב, א) שֶׁהַמַּנְהִיג בְּשׁוֹר פְּסוּלֵי הַמֻּקְדָּשִׁין לוֹקֶה, שֶׁאַף עַל פִּי שֶׁהוּא גּוּף אֶחָד עֲשָׂאוֹ הַכָּתוּב כִּשְׁנֵי גּוּפִין לִלְקוֹת עָלָיו. וְיֶתֶר פְּרָטֶיהָ, מְבֹאָרִים בְּפֶרֶק שְׁמִינִי מִמַּסֶּכֶת כִּלְאַיִם [שם רצז].
From the laws of the commandment is that which they, may their memory be blessed, said (see Sefer HaMitzvot, Negative Commandments 218 and Mishneh Torah, Diverse Species 9:7) that the obligation of this commandment from Torah writ is only with two species like the ox and the donkey — that one of them is pure and the second one impure, [such] that their natures are very distant from one another. But with two species that are [both] pure or impure — like an ox and a goat, or a donkey and horse — it is not forbidden from the Torah. Rather it is [only] rabbinically that any two species that would [constitute a case of] forbidden interbreeding are forbidden — and both [domesticated] beasts and [undomesticated] animals are included in the prohibition. And it is the same whether one plows with them or seeds or pulls a wagon with them. And so [too,] if one [person] was sitting in the wagon and one was leading [them] — both of them are lashed, because his sitting in the wagon [also] causes the animal to pull. (See Mishneh Torah, Diverse Species 9:9.) And even if a hundred [people] led together, all of them are lashed. And [about] that which they said that it is permissible to do all work with a person and an animal, as it states, “with an ox and a donkey” — and not with a person and a donkey or a person and an ox (see Mishneh Torah, Diverse Species 9:10) — the explanation of the matter is according to the root that we mentioned. As the joining of an animal is not distressing for a person, since there is no connection with it at all. And behold, it is like he is doing work with a tree or a stone; and [so] it does not at all come into the designation that we spoke about. And also from the matter of the commandment is that which Rabbi Yitschak said at the end of Makkot 22a, that one who leads an ox of those disqualified from the consecrated is lashed — even though it is one body, the verse made it like two bodies to be lashed for. And the rest of its details are explained in the eighth chapter of Kilayim. (See Tur, Yoreh Deah 297.)
וְנוֹהֵג אִסּוּר זֶה בְּכָל מָקוֹם וּבְכָל זְמַן בִּזְכָרִים וּנְקֵבוֹת. וְהָעוֹבֵר עַל זֶה וְזָרַע אוֹ חָרַשׁ אוֹ מָשַׁךְ אוֹ הִנְהִיג בְּכִלְאַיִם שֶׁהֵן שְׁנֵי מִינִין אֶחָד טָמֵא וְאֶחָד טָהוֹר, חַיָּב מַלְקוּת מִדְּאוֹרַיְתָא. וַאֲפִלּוּ הִנְהִיגָן כְּאֶחָד בְּקוֹל לְבַד, כְּדֶרֶךְ הַבְּהֵמוֹת שֶׁהוֹלְכוֹת לִפְעָמִים בְּגַעֲרַת בֶּן אָדָם חַיָּב מַלְקוּת, שֶׁנֶּאֱמַר יַחְדָּו. מִכָּל מָקוֹם דִּקְדְּקוּ זִכְרוֹנָם לִבְרָכָה בָּזֶה מִדִּבְרֵי הַכָּתוּב, לְחַיֵּב מַלְקוּת בְּדִבּוּר בְּלִי מַעֲשֶׂה. וְאִם בִּשְׁנֵי מִינִין טְמֵאִים אוֹ טְהוֹרִים, שֶׁהֵן כִּלְאַיִם בְּהַרְבָּעָה זֶה בָּזֶה, חַיָּב מַכַּת מַרְדּוּת מִדְּרַבָּנָן.
And this prohibition is practiced in every place and at all times by males and females. And one who transgresses this and seeds or plows or pulls or leads with a forbidden mixture — which are two species, one impure and one pure — is liable for lashes from Torah writ. And he is liable for lashes even if he led them together with his voice alone — like the way of animals that sometimes walk with the coaxing of people, as it is stated, “together” — in any case. They, may their memory be blessed, made a precise inference from the words of the verse to obligate lashes [even] with speech without a deed. And in [the case of] two species that were [both] impure or pure, that are forbidden to interbreeding with each other, he is rabbinically liable for lashes of rebellion.