To not leave the beast of his fellow falling under its load: That we have been warned that if we see a Jew whose donkey or other beast fell from the weight of its load or from another reason, or if he, himself, is crouching under his load (see Sefer HaMitzvot, Negative Commandments 270), that we should not leave him on the way and walk [away]; but [rather], we help him and lift up his beast with him, and we stay there until he has set up his load — either on his back or on his beast. And about this is it stated (Deuteronomy 22:4), “You shall not see the donkey of your brother, etc.” — and they said in the Sifrei here [that], “‘You shall not see the donkey, etc.’ is a negative commandment.”
And behold, one who transgresses this, and does not aid his fellow on the way, violates this negative commandment and the positive commandment mentioned in Parashat Mishpatim (Sefer HaChinukh 90), about the commandment of removing the load from upon the beast. And there, we elucidated the root of this commandment and all of its matter, as is our custom in this book — see it there. (See Tur, Yoreh Deah 272.)
שֶׁלֹּא לְהַנִּיחַ בֶּהֱמַת חֲבֵרוֹ נוֹפֶלֶת תַּחַת מַשָּׂאָהּ – שֶׁהֻזְהַרְנוּ שֶׁאִם נִרְאֶה אֶחָד מִיִּשְׂרָאֵל שֶׁנָּפַל לוֹ חֲמוֹרוֹ אוֹ בְּהֵמָה אַחֶרֶת מִכֹּבֶד הַמַּשָּׂא אוֹ בְּסִבָּה אַחֶרֶת, אוֹ שֶׁהוּא בְּעַצְמוֹ רוֹבֵץ תַּחַת מַשָּׂאוֹ (עי' רמב"ם בסהמ"צ לאוין ער) שֶׁלֹּא לְהַנִּיחוֹ בַּדֶּרֶךְ וְנֵלֵךְ, אֲבָל נַעַזְרֵהוּ וְנָקִים עִמּוֹ בְּהֶמְתּוֹ וְנַעֲמֹד שָׁם עַד שֶׁיְּתַקֵּן מַשָּׂאוֹ אוֹ עַל גַּבּוֹ אוֹ עַל בְּהֶמְתּוֹ, וְעַל זֶה נֶאֱמַר (דברים כב ד) לֹא תִרְאֶה אֶת חֲמוֹר אָחִיךָ וְגוֹ'. וְאָמְרוּ בְּסִפְרֵי (כאן) לֹא תִרְאֶה אֶת חֲמוֹר וְגוֹ', מִצְוַת לֹא תַעֲשֶׂה.
To not leave the beast of his fellow falling under its load: That we have been warned that if we see a Jew whose donkey or other beast fell from the weight of its load or from another reason, or if he, himself, is crouching under his load (see Sefer HaMitzvot, Negative Commandments 270), that we should not leave him on the way and walk [away]; but [rather], we help him and lift up his beast with him, and we stay there until he has set up his load — either on his back or on his beast. And about this is it stated (Deuteronomy 22:4), “You shall not see the donkey of your brother, etc.” — and they said in the Sifrei here [that], “‘You shall not see the donkey, etc.’ is a negative commandment.”
וְהִנֵּה הָעוֹבֵר עַל זֶה וְלֹא סִיַּע חֲבֵרוֹ בַּדֶּרֶךְ עוֹבֵר עַל לֹא תַעֲשֶׂה זֶה, וְעַל עֲשֵׂה הַנִּזְכָּר בְּפָרָשַׁת מִשְׁפָּטִים (מצוה פ) בְּמִצְוַת הֲסָרַת הַמַּשָּׂא מֵעַל הַבְּהֵמָה. וְשָׁם בֵּאַרְנוּ שֹׁרֶשׁ מִצְוָה זוֹ וְכָל עִנְיָנָהּ כְּמִנְהָגֵנוּ בְּסֵפֶר זֶה, תִּרְאֶנּוּ מִשָּׁם [יו"ד סימן רע"ב].
And behold, one who transgresses this, and does not aid his fellow on the way, violates this negative commandment and the positive commandment mentioned in Parashat Mishpatim (Sefer HaChinukh 90), about the commandment of removing the load from upon the beast. And there, we elucidated the root of this commandment and all of its matter, as is our custom in this book — see it there. (See Tur, Yoreh Deah 272.)