We should love all humans, even our enemies, not because they are friends but in order that they may be like friends. We should burn with love for all who are already our friends and pray for those who are still enemies that they might become our friends. When we love someone in the right way we make them a friend, one who is joined in some way to us in unity. If we lived the way we should, we would love our enemies in order that they might become our friends.

–Augustine, Commentary on the Epistle of John, 10.7.3