Lutheran theology explains these as the two great, yet diametrically opposed teachings of Scripture. The Law is taught as God's unwavering word of command and a condemnation of all that is sinful. The Gospel is taught as God's gracious word of promise, bringing forgiveness and reconciliation through the death and resurrection of Jesus Christ. Centered especially in the Pauline corpus, it was detailed in many writings by Martin Luther and summarized by American theologian C. F. W. Walther.