It was out of this profound religious experience of Luther—the depth of which is far from being plumbed in this verse—that his concept of grace was formulated, a concept which in its broad outline indicated the main lines of discussion for subsequent Protestant theology. Like Paul and Augustine before him, his theology was the outgrowth of an experience so traumatic that the whole course of his life was irrevocably transformed.‘Driven into a monastery by fear of the wrath of God and by the desire to earn divine forgiveness and approval by meritorious works, he discovered that it was impossible to secure peace of mind by such a method, and was finally led to believe that the only road to peace lay in repudiating all righteousness of his own, and depending wholly upon the free grace of God in Christ.’