Torah Portion: Mishpatim
If a man strikes his male or female slave with a rod, and [the slave] dies under his hand, [the death] must be avenged (Shemos 21:20).
It is a positive commandment to put to death by sword those who violate certain commandments of the Torah. This penalty is called by our Sages hereg, and it is an easy death, although strangulation is yet easier.
One of those executed by this death is a person who struck his slave, even if that slave was an eved canaani (a non-Jewish slave), and the slave died under his hand. It is thus written: [the death] must be avenged (Shemos 21:20), which means that his attacker is to be killed by the sword.
Among the roots of this commandment is the idea that God wished to uproot ruthlessness and cruelty from the midst of His holy people. The Torah therefore commanded that if anyone becomes so overwhelmed by such rage that he could beat to death his servant who is in his home and has no one to save him, then let the one who did this be put to death. Even though the servant was his purchased possession, and with the slave’s death he lost his own property, nevertheless he is to be slain, since he allowed his rage to prevail over his spirit to such an extent.
One who transgresses this [commandment] and does not impose justice on him, if it was in his power to do so, has violated a positive commandment, and his punishment is great, for he thereby causes obstacles for people.