After an introduction on Luther’s conception of the new man and the relation between justification and sanctification, the author probes some of his writings, especially the «Sermon on Good Works», to ascertain which are the good works in Luther’s theology, which is their place and their value. The last section, on «Christian’s historical responsibility and creativity», makes clear how, on the basis of his own faith, the believer is called to respond creatively and responsibly to the demands of history, beyond positive law and even Moses’ Decalogue, and witness to God’s presence among mankind and cooperate with Him in the re-creation of the world and the good of mankind (pp. 247-276).