What is the comparison to a horse or mule?
Rashi: It does not distinguish between one who benefits it or harms it. When you put a bridle on it, it closes its mouth and chews on the bit. When you comb it to beautify it, you need to close its mouth with a bit and afflict it with a harness!
Radak: An animal 1 does not understand whether you come to harm it. You must close its mouth with a bit and a harness, lest it bite you. Words do not help; you need to do an act to stop it from doing evil. Do not be like this - rather, repent to Hashem!
Malbim: Do not be like a horse and mule, that the only way to stop them from veering from the path, or damaging with their mouths, is via a bit and harness. You should understand from a wink! Man is compared to a horse and its rider, for his physicality is like that of animals. However, the intellectual Nefesh in man conducts the physicality and binds it. When the physicality rebels, he must afflict it for the sake of the 'rider'. His physicality should be better than an animal, and realize that the afflictions are for the man himself, the Neshamah, lest the body harm it!
Radak: It mentions a horse and mule, for people ride on them, and need a harness to stop them from going where they want, or damaging with their mouths.
Why does it say "Bal Kerov Elecha"?
Rashi: When you beautify it, you must muzzle and harness it, lest it approach you [Radak - to bite you].
What is the meaning of "Edyo Livlom"?
Rashi: When you comb it to beautify it, you need to close and harness its mouth lest it approach you [to harm you].
Rashi citing Menachem: Livlom is an expression of content; the same applies to "Al Belimah" (Iyov 26:7).
Radak: Edyo is its mouth, like "ha'Masbi'a ba'Tov Edyech" (103:5).
