It’s often said that the phrase, “Love the sinner; hate the sin” is from Gandhi. Mark Driscoll and Gary Breshears said it in “Death by Love” so it must be true! (Good book, by the way). However, a good 1600 years before Gandhi, Augustine said it in his “The City of God“, book 14, chapter 6 (read this whole quote – it unpacks it well).
…Wherefore the man who lives according to God, and not according to man, ought to be a lover of good, and therefore a hater of evil. And since no one is evil by nature, but whoever is evil is evil by vice, he who lives according to God ought to cherish towards evil men a perfect hatred, so that he shall neither hate the man because of his vice, nor love the vice because of the man, but hate the vice and love the man. For the vice being cursed, all that ought to be loved, and nothing that ought to be hated, will remain.
Moreover, what I have now said in regard to abstaining from wanton looks should be carefully observed, with due love for the persons and hatred of the sin, in observing, forbidding, reporting, proving, and punishing of all other faults.
And perhaps elsewhere. It comes from Augustine’s conviction that God created no evil, and so even evil people, though corrupted, are in some senses good, and we should love them on that account.