It would be nonsense to urge men to love their oppressors in an affectionate sense. “Love” in this connection means understanding good will. There are three words for love in the Greek New Testament. First, there is eros. In Platonic philosophy eros meant the yearning of the soul for the realm of the divine. It has come now to mean a sort of aesthetic or romantic love. Second, there is philia. It meant intimate affectionateness between friends. Philia denotes a sort of reciprocal love: the person loves because he is loved. When we speak of loving those who oppose us we refer to neither eros nor philia; we speak of a love which is expressed in the Greek word agape. Agape means nothing sentimental or basically affectionate; it means understanding, redeeming good will for all men, an overflowing love which seeks nothing in return. It is the love of God working in the lives of men. When we love on the agape level we love men not because we like them, not because their attitudes and ways appeal to us, but because God loves them. Here we rise to the position of loving the person who does the evil deed while hating the deed he does.
— MLK, Nonviolence and Racial Justice, an article in Christian Century, February 1957