Adam Clarke on Exodus 21:28

If an ox gore a man - It is more likely that a bull is here intended, as the word signifies both, see Exo 22:1; and the Septuagint translate the שור shor of the original by ταυρος, a bull. Mischief of this kind was provided against by most nations. It appears that the Romans twisted hay about the horns of their dangerous cattle, that people seeing it might shun them; hence that saying of Horace. Sat., lib. i., sat. 4, ver. 34: Faenum habet in cornu, longe fuge. "He has hay on his horns; fly for life!" The laws of the twelve tables ordered, That the owner of the beast should pay for what damages he committed, or deliver him to the person injured. See Clarke's note on Exo 22:1.

His flesh shall not be eaten - This served to keep up a due detestation of murder, whether committed by man or beast; and at the same time punished the man as far as possible, by the total loss of the beast.