[K:NWTS 20/2 (Sep 2005) 10-11]
The soul which with a firm faith cleaves to the promises of God is united with them, absorbed by them, penetrated, saturated, inebriated by their power. If the touch of Christ was healing, how much more does that most tender touch in the spirit, that absorption in the Word convey to the soul all the qualities of the Word so that it becomes trustworthy, peaceable, free, full of every good, a true child of God. From this we see very easily why faith can do so much and no good work is like unto it, for no good work comes from God's Word like faith. No good work can be within the soul, but the Word and faith reign there. What the Word is that the soul is, as iron becomes fire-red through union with the flame. Plainly then faith is enough for the Christian man. He has no need for works to be made just. Then is he free from the law.
But he is not therefore to be lazy or loose. Unless a man is already a believer and a Christian, his works have no value at all. They are foolish, idle, damnable sins, because when good works are brought forward as ground for justification, they are no longer good. Understand that we do not reject good works, but praise them highly. The apostle Paul said, "Let this mind be in you which was also in Christ Jesus, who being on an equality with God emptied himself, taking the form of a servant, and becoming obedient unto death." Paul means that when Christ was fully in the form of God, abounding in all things, so that he had no need of any work or any suffering to be saved, he was not puffed up, did not arrogate to himself power, but rather in suffering, working, enduring, and dying made himself like other men, as if he needed all things and were not in the form of God. All this he did to serve us. When God in his sheer mercy and without any merit of mine has given me such unspeakable riches, shall I not then freely, joyously, wholeheartedly, unprompted do everything I know will please him? I will give myself as a sort of Christ to my neighbor as Christ gave himself for me.
From The Freedom of the Christian Man cited by Roland Bainton in his classic study of the life of Luther, Here I Stand: A Life of Martin Luther (New York and Nashville: Abingdon Press, 1950) 230-31.