How servants and masters are to be admonished.
(Admonition 6). Differently to be admonished are servants and masters. Servants, to wit, that they ever keep in view the humility of their condition; but masters, that they lose not recollection of their nature, in which they are constituted on an equality with servants. Servants are to be admonished that they despise not their masters, lest they offend God, if by behaving themselves proudly they gainsay His ordinance: masters, too, are to be admonished, that they are proud against God with respect to His gift, if they acknowledge not those whom they hold in subjection by reason of their condition to be their equals by reason of their community of nature. The former are to be admonished to know themselves to be servants of masters; the latter are to be admonished to acknowledge themselves to be fellow-servants of servants. For to those it is said, Servants, obey your masters according to the flesh; and again, Let as many servants as are under the yoke count their masters worthy of all honour; but to these it is said, And you, masters, do the same things unto them, forbearing threatening, knowing that both their and your Master is in heaven.
Source: Pastoral Rule (New Advent)