Luther's role in the Reformation was crucial, arguably more important than that of any other single individual. He was its guiding spirit, a bloody-minded genius providing hundreds and thousands of men and woman with the inspiration necessary to challenge the temporal and spiritual dominance of the Church of Rome. It fell to others to shape the contours of the earthshaking revolution he had unleashed, but they still found themselves working in the towering shadow cast over them by the renegade monk of Wittenberg.
Luther's primary grievance against Rome was theological. His doctrine of justification by faith alone immediately put him at odds with the Church. He held that individual believers could only be justified, or made right with God, through the channel of faith. There was absolutely nothing that a Christian could do to make this happen; it depended entirely on the free gift of divine grace. This was the only way that Christian believers could ever be reconciled with God.
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