
Gregory the Great
Catena Aurea · Matthäusevangelium 7
Therefore all things whatsoever ye would that men should do to you, do ye even so to them: for this is the Law and the Prophets.
(Mor. x. 6.) He that thinks he ought to do to another as he expects that others will do to him, considers verily how he may return good things for bad, and better things for good.