The Archbishop of Canterbury, Rowan Williams (who has announced that he is stepping down) has some perceptive comments about Luther, the Reformation, and the Theology of the Cross:
“The Reformation put a question of the utmost gravity to all Christians, a question about the continuity and dependability of human response to God. It affirmed that the Church was capable of error; that no amount of scholastic tidiness could guarantee fidelity to God; that there was in the Church no secure locus of unquestionable authority. It pointed eloquently to human brokenness, the failure of reason and order. But it did so only to claim triumphantly that the Church’s security lay in this very failure, in the insecurity and un-rootedness which drove it always back to its spring in the Word made broken flesh. Against the self-sufficiency of Christendom is set – rightly and decisively – the cross. To Christians looking for a sign, an assurance, it offered only the ‘sign of the Son of Man’, God hidden in the death of Christ… Luther is a reminder to Catholic and Protestant alike that the strength of Christianity is its refusal to turn away from the central and unpalatable facts of human self-destructiveness; that it is there, in the bitterest places of alienation, that the depth and scope of Christ’s victory can be tasted, and the secret joy which transforms all experience from within can come to birth, the hidden but all-pervading liberation.” (p. 160-61)
The quotation is from his book Wound of Knowledge: Christian Spirituality from the New Testament to St. John of the Cross.