Well, okay, but isn't the relevant context his book Strength to Love, and, you know, his entire ethos? Here's a few of quotes from StL, but you can find similar sentiment in dozens or hundreds of places in his collected speeches and writings.
Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that. Hate multiplies hate, violence multiplies violence, and toughness multiplies toughness in a descending spiral of destruction ... The chain reaction of evil--hate begetting hate, wars producing more wars -- must be broken, or we shall be plunged into the dark abyss of annihilation.and
When we look beneath the surface, beneath the impulsive evil deed, we see within our enemy-neighbor a measure of goodness and know that the viciousness and evilness of his acts are not quite representative of all that he is. We see him in a new light. We recognize that his hate grows out of fear, pride, ignorance, prejudice, and misunderstanding, but in spite of this, we know God's image is ineffably etched in being. Then we love our enemies by realizing that they are not totally bad and that they are not beyond the reach of God's redemptive love.and
love is the only force capable of transforming an enemy into a friend. We never get rid of an enemy by meeting hate with hate; we get rid of an enemy by getting rid of enmity. By its very nature, hate destroys and tears down; by its very nature, love creates and builds up. Love transforms with redemptive power.and
We shall match your capacity to inflict suffering by our capacity to endure suffering. We shall meet your physical force with soul force. Do to us what you will, and we shall continue to love you. We cannot in all good conscience obey your unjust laws because noncooperation with evil is as much a moral obligation as is cooperation with good. Throw us in jail and we shall still love you. Bomb our homes and threaten our children, and we shall still love you. Send your hooded perpetrators of violence into our community at the midnight hour and beat us and leave us half dead, and we shall still love you. But be ye assured that we will wear you down by our capacity to suffer. One day we shall win freedom but not only for ourselves. We shall so appeal to your heart and conscience that we shall win you in the process and our victory will be a double victory.and
no one should rejoice at the death or defeat of a human being.Seems relevant!
Update: Mystery solved, I'd say.