Note: On another historical note, keep in mind that on May 24, 1738, John Wesley was converted when his heart was "strangely warmed," as he heard this document read at a meeting on Aldersgate Street, London. 

Now, here's Luther's text:
This epistle is in truth the most important document in the New Testament, the gospel in its purest expression. Not only is it well worth a Christian's while to know it word for word by heart, but also to meditate on it day by day. It is the soul's daily bread, and can never be read too often or studied too much. The more you probe into it the more precious it becomes, and the better its flavor. God helping me, I shall try my best to make this Preface serve as an introduction which will enable everyone to understand it in the best possible way. Hitherto, this epistle has been smothered with comments and all sorts of irrelevancies; yet, in essence, it is a brilliant light, almost enough to illumine the whole Bible.
The first thing needed is to master the terminology. We must learn what St. Paul means by such words as law, sin, grace, faith, righteousness, flesh, spirit, and the like; otherwise we shall read and only waste our time. You must not understand the term LAW in its everyday sense as something which explains what acts are permitted or forbidden. This holds for ordinary laws, and you keep them by doing what they enjoin, although you may have no heart in it. But God judges according to your inmost convictions; His law must be fulfilled in your very heart, and cannot be obeyed if you merely perform certain acts. Its penalties do indeed apply to certain acts done apart from our inmost convictions, such as hypocrisy and lying. Psalm 117 declares that all men are liars, because no one keeps God's law from his heart; nor can he do so, for to be averse to goodness and prone to evil are traits found in all men. If we do not choose goodness freely, we do not keep God's law from the heart. Then sin enters in, and divine wrath is incurred even though, to outward appearance, we are doing many virtuous works and living an honorable life.
In Chapter 2, St. Paul therefore asserts that the Jews are all sinners. He says that only those who keep the law are righteous in God's eyes, his point being that no one keeps the law by "works." Rather, Paul says to the Jews, "You teach us not to commit adultery, but you commit adultery yourselves, since you do the very things which you condemn." It is as if he were to say, To outward appearance, you observe the law scrupulously, condemning those who do not observe it, and being quick to teach one and all. You see the splinter in the other man's eye, but are unaware of the timber in your own. Granted that, in appearance and conduct, you observe the law, owing to your fear of punishment or hope of reward, yet you do nothing from free choice and out of love for the law, but unwillingly and under compulsion; were there no law, you would rather do something else. The logical conclusion is that, in the depths of your heart, you hate the law. What is the use of teaching others not to steal if you are a thief at heart yourself and, if you dared, would be one in fact? Of course, the outer conduct of this kind is not continued for long by humbugs of this kind. It follows that, if you teach others but not your own selves, you do not know what you teach and have not rightly understood the nature of the law. Nay, the law increases your guilt, as Paul says in Chapter 5. A man only hates the law the more, the more it demands what he cannot perform.
That is why, in Chapter 7, Paul calls the law spiritual; spiritual because, if the law were corporeal, our works would meet its demands. Since it is spiritual, however, no one keeps it, unless everything you do springs from your inmost heart. Such a heart is given us only by God's spirit, and this spirit makes us equal to the demands of the law. Thus we gain a genuine desire for the law, and then everything is done with willing hearts, and not in fear or under compulsion. Therefore, because that law is spiritual when it is loved by hearts that are spiritual, and demands that sort of mind, if that spirit is not in our hearts, sin remains; a grudge abides together with hostility to the law, although the law itself is right and good and holy.
Therefore, familiarize yourself with the idea that it is one thing to do what the law enjoins and quite another to fulfill the law. All that a man does or ever can do of his own free will and strength is to perform the works required by the law. Nevertheless, all such works are vain and useless as long as we dislike the law and feel it a constraint. That is Paul's meaning in Chapter 3 when he says, "Through the works of the law shall no man be justified before God." It is obvious--is it not?-- that the sophisticators wrangling in the schools are misleading when they teach us to prepare ourselves for grace by our works. How can anyone use works to prepare himself to be good when he never does a good work without a certain reluctance or unwillingness in his heart? How is it possible for God to take pleasure in works that spring from reluctant and hostile hearts?
To fulfill the law, we must meet its requirements gladly and lovingly; live virtuous and upright lives without the constraint of the law, and as if neither the law nor its penalties existed. But this joy, this unconstrained love, is put into our hearts by the Holy Spirit, as St. Paul says in Chapter 5. But the Holy Spirit is given only in, with, and through faith in Jesus Christ, as Paul said in his opening paragraph. Similarly, faith itself comes only through the word of God, the gospel. This gospel proclaims Christ as the Son of God; that He was man; that He died and rose again for our sakes, as Paul says in Chapters 3, 4, and 10.
We reach the conclusion that faith alone justifies us and fulfills the law; and this because faith brings us the spirit gained by the merits of Christ. The spirit, in turn, gives us the happiness and freedom at which the law aims, and this shows that good works really proceed from faith. That is Paul's meaning in Chapter 3 when, after having condemned the works of the law, he sounds as if he had meant to abrogate the law by faith; but says that, on the contrary, we confirm the law through faith, i.e. we fulfill it by faith.
The word SIN in the Bible means something more than the external works done by our bodily action. It means all the circumstances that act together and excite or incite us to do what is done; in particular, the impulses operating in the depths of our hearts. This, again, means that the single term, "doing," includes the case where a man gives way completely and falls into sin. Even where nothing is done outwardly, a man may still fall into complete destruction of body and soul. In particular, the Bible penetrates into our hearts and looks at the root and the very source of all sin, i.e., unbelief in the depth of our heart. just as faith alone gives us the spirit and the desire for doing works that are plainly good, so unbelief is the sole cause of sin; it exalts the flesh, and gives the desire to do works that are plainly wrong, as happened in the case of Adam and Eve in the garden of Eden, Genesis 3.
Christ therefore singled out unbelief and called it sin. In John 16, He says, The spirit will convict the world of sin because they do not believe in me. Similarly, before good or evil works are performed, and before they appear as good or evil fruits, either faith or unbelief must be already in our hearts. Here are the roots, the sap and the chief energy of all sin. This is what the Bible calls the head of the serpent and of the old dragon, which Christ, the seed of the woman, must crush, as was promised to Adam.
The words GRACE and GIFT differ inasmuch as the true meaning of grace is the kindness of favor which God bears toward us of His own choice, and through which He is willing to give us Christ, and to pour the Holy Spirit and His blessings upon us. Paul makes this clear in Chapter 5 when he speaks of the grace and favor of Christ, and the like. Nevertheless, both the gifts and the spirit must be received by us daily, although even then they will be incomplete, for the old desires and sins still linger in us and strive against the spirit, as Paul says in Romans 7 and Galatians 5. Again, Genesis 3 speaks of the enmity between the woman's children and the serpent's brood. Yet grace is sufficient to enable us to be accounted entirely and completely righteous in God's sight, because His grace does not come in portions and pieces, separately, like so many gifts; rather, it takes us up completely into its embrace for the sake of Christ our mediator and intercessor, and in order that the gifts may take root in us.
This point of view will help you to understand Chapter 7, where Paul depicts himself as still a sinner; and yet, in Chapter 8, [he] declares that no charge is held against those who are "in Christ," because of the spirit and the (still incomplete) gifts. Insofar as our flesh is not yet killed, we are still sinners. Nevertheless insofar as we believe in Christ, and begin to receive the spirit, God shows us favor and goodwill. He does this to the extent that He pays no regard to our remaining sins and does not judge them; rather He deals with us according to the faith which we have in Christ until sin is killed.
FAITH is not something dreamed, a human illusion, although this is what many people understand by the term. Whenever they see that it is not followed either by an improvement in morals or by good works, while much is still being said about faith, they fall into the error of declaring that faith is not enough, that we must do "works" if we are to become upright and attain salvation. The reason is that, when they hear the gospel, they miss the point; in their hearts, and out of their own resources, they conjure up an idea which they call "belief," which they treat as genuine faith. All the same, it is but a human fabrication, an idea without a corresponding experience in the depths of the heart. It is therefore ineffective and not followed by a better kind of life.
Faith, however, is something that God effects in us. It changes us and we are reborn from 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. Oh, 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.
Faith is a living and unshakeable confidence, a belief in the grace of God so assured that a man would die a thousand deaths for its sake. This kind of confidence in God's grace, this sort of knowledge of it, makes us joyful, high-spirited and eager in our relations with God and with all mankind. That is what the Holy Spirit effects through faith. Hence the man of faith, without being driven, willingly and gladly seeks to do good to everyone, serve everyone, suffer all kinds of hardships, for the sake of the love and glory of the God who has shown him such grace. It is impossible, indeed, to separate works from faith, just as it is impossible to separate heat and light from fire. Beware, therefore, of wrong conceptions of your own, and of those who talk nonsense while thinking they are pronouncing shrewd judgments on faith and works whereas they are showing themselves the greatest of fools. Offer up your prayers to God, and ask Him to create faith in you; otherwise you will always lack faith, no matter how you try to deceive yourself, or what your efforts and ability.
RIGHTEOUSNESS means precisely the kind of faith we have in mind, and should properly be called "divine righteousness," the righteousness which holds good in God's sight, because it is God's gift and shapes a man's nature to do his duty to all. By his faith, he is set free from sin, and he finds delight in God's commandments. In this way, he pays God the honor that is due to Him, and renders Him what he owes. He serves his fellows willingly according to his ability, so discharging his obligations to all men. Righteousness of this kind cannot be brought about in the ordinary course of nature, by our own free will or by our own powers. No one can give faith to himself, nor free himself from unbelief; how, then, can anyone do away with even his smallest sins? It follows that what is done in the absence of faith on the one hand, or in consequence of unbelief on the other, is naught but falsity, self-deception and sin (Romans 14), no matter how well it is gilded over.
FLESH and SPIRIT must not be understood as if flesh had only to do with moral impurity and spirit only with the state of our hearts. Rather, flesh, according to St. Paul, as also according to Christ in John 3, means everything that is born from the flesh, i.e. the entire self, body and soul, including our reason and all our senses. This is because everything in us leans to the flesh. It is therefore appropriate to call a man "carnal" when, not having yet received grace, he gibbers and jabbers cheerfully about the high things of the spirit in the very way which Galatians 5 depicts as the works of the flesh, and calls hypocrisy and hatred works of the flesh. Moreover, Romans 8 says that the law is weakened by the flesh. This is not said simply of moral impurity, but of all sins. In particular, it is said of lack of faith, which is a kind of wickedness more spiritual in character than anything else.
On the other hand, the term spiritual is often applied to one who is busied with the most outward of works, as when Christ washed His disciples' feet, and when Peter went sailing his boat and fishing. Hence the term "flesh" applies to a person who, in thought and in fact, lives and labors in the service of the body and the temporal life. The term "spirit" applies to a person who, in thought and fact, lives and labors in the service of the spirit and of the life to come. Unless you give these terms this connotation, you will never comprehend Paul's epistle to the Romans, nor any other book of Holy Scripture. Beware then of all teachers who use these terms differently, no matter who they may be, whether Jerome, Augustine, Ambrose, Origen, or their like; or even persons more eminent than they.