Every Christian is by faith so exalted above all things that in spiritual power he is completely lord of all. Nothing whatever can do him any hurt, but all things are subject to him and are compelled to be subservient to his salvation...This is a spiritual power ruling in the midst of enemies and mighty in the midst of distresses. And it is nothing else than that strength is made perfect in weakness, and in all things I am able to gain salvation, so that even the cross and death are compelled to serve me and work together for salvation. For this is a high and illustrious dignity, a true and almighty power, a spiritual empire, in which there is nothing so good, nothing so bad as not to work together for my good if only I believe...A Christian man needs no work, no law for salvation, for by faith he is free from all law and in perfect freedom does gratuitously all he does, seeking neither profit nor salvation, but only what is well-pleasing to God, since by the grace of God he is already satisfied and saved through his faith.

Luther (in Martin Luther-the Man and His Work by Arthur McGiffert, p. 174)