“Transvaluation of values,” a term derived from Nietzsche (who derided Christianity’s embrace of the weak), is the heart of Niebuhr’s perspective on the cross. He uses the phrase repeatedly in his writings. We find its meaning whenever he speaks about God’s mercy and love in relation to Jesus Christ, especially in his sermons and several of his books. For Niebuhr the revelation of God’s transcendent love hidden in Jesus’ suffering on the cross is not simply the “keystone” of the Christian faith; it is the very key to history itself.[13]