לִטְעֹן הַמַּשָּׂא שֶׁנָּפַל עִם חֲבֵרוֹ – שֶׁנִּצְטַוִּינוּ לַעֲזֹר אֶת אַחֵינוּ כְּשֶׁיִּהְיוּ צְרִיכִים לָתֵת הַמַּשָּׂא עַל הַבְּהֵמָה אוֹ עַל הָאִישׁ וְאֵין מִי שֶׁיַּעַזְרֵם עַל הַדָּבָר, וְעַל זֶה נֶאֱמַר (דברים כב ד) הָקֵם תָּקִים עִמּוֹ. וְזֶה יִקְרְאוּ זִכְרוֹנָם לִבְרָכָה (ב"מ לב א) טְעִינָה. וְאָמְרוּ זִכְרוֹנָם לִבְרָכָה (שם) שֶׁנּוֹטְלִין שָׂכָר עַל הַטְּעִינָה, אֲבָל עַל הַפְּרִיקָה, כְּלוֹמַר לַעֲזֹר אֶת אָחִיו לִפְרֹק הַמַּשָּׂא מֵעָלָיו אוֹ מֵעַל בְּהֶמְתּוֹ הַחִיּוּב הַזֶּה הוּא עָלֵינוּ לַעֲשׂוֹתוֹ בְּחִנָּם. To load the load that has fallen [together] with his fellow: That we were commanded to help our brothers when they need to place the load on the beast or on the person, and there is not someone to help them with the thing. And about this it states (Deuteronomy 22:4), “you shall surely pick it up with him.” And this, they, may their memory be blessed, called (Bava Metzia 32a) “loading (teinah).” And [there] they, may their memory be blessed, said that we [can] take payment for loading, but for the unloading — meaning to say, to help his brother to unload the load from upon him or from upon his beast — this obligation is upon us to do for free.
וּמִשָּׁרְשֵׁי מִצְוָה זוֹ וּקְצָת דִּינֶיהָ כָּתַבְתִּי בְּמִצְוַת פְּרִיקָה בְּסֵדֶר מִשְׁפָּטִים, בְּמִצְוַת לְהָסִיר הַמַּשָּׂא מֵעַל הַבְּהֵמָה (מצוה פ). וְכָל עִנְיָנָהּ תַּגִּיד עָלֶיהָ חֲבֶרְתָּהּ. And I have written about the roots of this commandment and a few of its laws, with regards to the commandment of unloading in the Order of Mishpatim, about the commandment to remove the load from upon the beast (Sefer HaChinukh 80). And its fellow (that commandment) speaks about all of [the current commandment’s] matter.