This tells me only of "the ass of your brother." Whence do I derive (the same for) the ass of your foe? From (Shemoth 23:5) "the ass of your foe." If so, why is it written (here) "your brother"? Scripture (there) speaks anent the evil inclination (i.e., Assist not only the ass of your brother, but even the ass of your foe — against the protestations of your evil inclination.)
"on the way": and not in the stall — whence it was ruled: If it were found (fallen) in the stall, the obligation does not obtain; if in the public thoroughfare, it does.