Compare the marginal references. In other kinds of labor the oxen were usually muzzled. When driven to and fro over the threshing-floor in order to stamp out the grain from the chaff, they were to be allowed to partake of the fruits of their labors.
Related Commentaries of Deuteronomy 25:4
Deuteronomy 25:4
4 Thou shalt not muzzle the ox when he treadeth out the corn.