Commentaire sur les Romains, Préface.
Martin Luther
Faith, however, is something that God effects in us. It changes us and we are reborn form God, John 1. Faith puts the old Adam to death and makes us quite different men in heart, in mind, and in all our powers; and it is accompanied by the Holy Spirit. O, when it comes to faith, what a living, creative, active, powerful thing it is. It cannot do other than good at all times. It never waits to ask whether there is some good work to do, rather, before the question is raised, it has done the deed, and keeps on doing it. A man not active in this way is a man without faith. He is groping about for faith and searching for good works, but knows neither what faith is nor what good works are. Nevertheless, he keeps on talking nonsense about faith and good works.
Commentary on Romans, Preface.
Martin Luther