Augustine of Hippo

A bishopric necessarily pertains to him who is the head of the household. It is a superintendence of the faith of the members of the household, lest any fall into heresy. It extends to the wife, to a son or a daughter; it extends also to a slave, for he has also been redeemed at so great a price. The apostolic teaching assumes the placement of the master above the slave and the slave beneath the master, but Christ has given the same price for each of them. Do not neglect even the lowliest among your household.