Parashas Mishpatim · Passuk 23:5
Chabad.org — English translation + Rashi
Torah Temimah points to Bava Metzia 32a (verified).
Sefaria — Exodus 23:5
Sefaria — Bava Metzia 32a
E-Daf — Bava Metzia 32a
English: If the owner walked away and sat down, saying, “Since the mitzvah is upon you, unload if you wish,” he is exempt, because the verse says “with him.” But if the owner is elderly or ill, he remains obligated.
On the daf / in context: See the cited source for the full section.
Derash on the verse.