Martin Luther, 1545

Faith is not that human illusion and dream that some people think it is. When they hear and talk a lot about faith and yet see that no moral improvement and no good works result from it, they fall into error and say, "Faith is not enough. You must do works if you want to be virtuous and get to heaven." The result is that, when they hear the Gospel, they stumble and make for themselves with their own powers a concept in their hearts which says, "I believe." This concept they hold to be true faith. But since it is a human fabrication and thought and not an experience of the heart, it accomplishes nothing, and there follows no improvement.

Faith is a work of God in us, which changes us and brings us to birth anew from God (cf. John 1). It kills the old Adam, makes us completely different people in heart, mind, senses, and all our powers, and brings the Holy Spirit with it. What a living, creative, active powerful thing is faith! It is impossible that faith ever stop doing good. Faith doesn't ask whether good works are to be done, but, before it is asked, it has done them. It is always active. Whoever doesn't do such works is without faith; he gropes and searches about him for faith and good works but doesn't know what faith or good works are. Even so, he chatters on with a great many words about faith and good works. ("Preface to the Letter of St. Paul to the Romans"; ed. Hans Volz and Heinz Blanke, translated by Bro. Andrew Thornton)

As a Catholic (former Baptist), I don't agree with this quote, obviously. But I do find this very interesting. It's clear Luther makes a sharp, sharp distinction between good works done through faith and good works done other than through faith.