Martin Luther’s doctrine of justification is all too often assumed to be the same doctrine that later wound up in the Reformed Orthodox creeds. This sola fide (the one of Reformed Orthodoxy) tends to be read back into the magisterial Reformers, and in this manner the nuances of the original Reformation sola fide are missed.
The excerpts below come from Martin Luther’s introduction and summary of the book of Romans. Martin Luther, Commentary on Romans, trans. J. Theodore Mueller (Grand Rapids: Kregel Classic, Zondervan, 1954).
Notice that Luther’s notion of justifying righteousness is faith itself because faith satisfies the law. Luther’s notion of justifying righteousness, then, was not Christ’s active and passive obedience, as in much of the Reformed versions of the doctrine of imputation.
Furthermore, Luther’s fundamental understanding of justification is one of being “made righteous” by God’s granting of faith precisely because faith is transformational to the core of our hearts. Luther’s understanding of “none are righteous,” is this: None are righteous apart from the heart transplant of faith, but with that transforming grace, people can be made righteous. Luther’s understanding of “the works of the law” (pejoratively referred to today as works righteousness) is this: The works of the law are works done without transforming grace. Good works, on the other hand, for Luther, are those done by the power of grace worked in the heart.
Luther’s entire paradigm from which he affirms that man is justified by faith alone is quite different from today’s Protestant versions of sola fide, as you will see if you read excerpts from Luther’s summary of the book of Romans below.
To begin with we must have knowledge of its language and know what St. Paul means by the words, law, sin, grace, faith, righteousness, flesh, spirit, etc., otherwise no reading of it has any value (xiii).
If the law were for the body, it could be satisfied with works; but since it is spiritual, no one can satisfy it, unless all that you do is done from the bottom of the heart. But such a heart is given only by God’s Spirit, who makes man equal to the law, so that he acquires a desire for the law in his heart, and henceforth does nothing out of fear and compulsion, but everything out of a willing heart (xiv).
Accustom yourself, then, to this language, and you will find that doing the works of the law and fulfilling the law are two very different things. The work of the law is everything that one does, or can do toward keeping the law of his own free will or by his own powers. … That is what St. Paul means in chapter 3, when he says, “By the works of the law no man becomes righteous before God” (xv).
To fulfill the law however, is to do its works with pleasure and love, and to live a godly and good life of one’s own accord without the compulsion of the law. This pleasure and love for the law is put into the heart by the Holy Ghost, as he says in chapter 5. But the Holy Ghost is not given except in, with and by faith in Jesus Christ, as he says in the introduction; and faith does not come, save only through God’s Word or Gospel, which preaches Christ, that He is God’s Son and a man, has died and risen again for our sakes, as he says in chapters 3, 4, and 10.
Hence it comes that faith alone makes righteous and fulfils the law; for out of Christ’s merit, it brings the Spirit, and the Spirit makes the heart glad and free, as the law requires that it shall be (xv).
And the scriptures look especially into the heart and have regard to the root and source of all sin, which is unbelief in the inmost heart. As, therefore, faith alone makes righteous, and brings the Spirit, and produces pleasure in good, eternal works, so unbelief alone commits sin, and brings up the flesh, and produces in bad external works, as happened to Adam and Eve in Paradise (xvi).
Faith, however, is a divine work in us. It changes us and makes us to be born anew of God (John 1); it kills the old Adam and makes altogether different men, in heart and spirit and mind and powers, and it brings with it the Holy Ghost (xvii) … and this is the work of the Holy Ghost in faith. Hence a man is ready and glad, without compulsion, to do good to everyone, to serve everyone, to suffer everything, in love and praise to God, who has shown him this grace; and thus it is impossible to separate works from faith, quite as impossible as to separate heat and light fires (xvii).
Righteousness, then, is such a faith and is called “God’s righteousness,” or “the righteousness that avails before God,” because God gives it and counts it as righteousness for the sake of Christ, our Mediator, and makes a man give to every man what he owes him” (xvii).
… moreover, the law works wrath rather than grace, because no one keeps it out of love for it and pleasure in it, so that what comes by the works of the law is disgrace rather than grace. Therefore, faith alone must obtain the grace promised to Abraham … (xx).
There is sin; but it is no longer counted for condemnation, because of the faith that strives against it (xxi).
… but we are under the law when, without grace, we occupy ourselves in the work of the law. …. Grace, however, makes the law dear to us, and then sin is no more there, and the law is no longer against us, but with us. This is the true freedom from sin and the law, of which he writes, down to the end of the chapter, saying that it is liberty only to do good with pleasure and live a good life without the compulsion of the law. Therefore this liberty is a spiritual liberty, which does not abolish the law, but presents what the law demands; namely, pleasure and love. Thus the law is quieted and no longer drives men or makes demands of them. (xxii)
Therefore a man must have something else than the law, and more than the law, to make him righteous and save him. But they who do not rightly understand the law are blind; they go ahead, in their presumption, and think to satisfy the law with their works, not knowing what the law demands, viz., a willing and happy heart. (xxiii).