There is no effective rational answer to the challenge: "But give me a reason why I should love someone who does not deserve it." Love is the highest thing. There can be no higher reason to justify it.
Peter KreeftSin comes from not realizing God's love. Sin comes from thinking ourselves only as sinners, while overcoming sin comes from thinking ourselves as overcomers. We act our our perceived identities.
Peter KreeftWe modern egalitarians are tempted to the primal sin of pride in the opposite way from the ancients. The old, aristocratic form of pride was the desire to be better than others. The new, democratic form is the desire not to have anyone better than yourself. It is just as spiritually deadly and does not even carry with it the false pleasure of gloating superiority.
Peter KreeftBut how can we love someone if we don't like him? Easy-we do it to ourselves all the time. We don't always have tender, comfortable feelings about ourselves; sometimes we feel foolish, stupid, asinine, or wicked. But we always love ourselves: we always seek our own good. Indeed, we feel dislike toward ourselves, we berate ourselves, precisely because we love ourselves; because we care about our good, we are impatient with our bad.
Peter Kreeft