He also made another change in Romans. Romans 4:15 states,
...because the law brings about wrath; for where there is no law there is no transgression.
Yet in his German translation, Martin Luther added the word ‘only’ before the term ‘wrath’ to Romans 4:15
This presumably was to attempt to justify his position to discredit the law.
Why shouldn't the "law" be discredited? It cannot bring salvation but DOES only bring down the wrath of God against all sin. But I looked up the dispute at http://beggarsallreformation.blogspot.com/search?q=romans+4%3A15, a very helpful site for your future reference prior to using that Luther card again. In it we learn:
On the other hand, is the sense of the meaning changed by using the word "only"? Luther states in The Bondage of the Will, "Again, since the law is the power of sin [I Cor. 15:56] in that it serves only to reveal and not to remove sin, it makes the conscience guilty before God, and threatens it with wrath. That is what Paul means when he says: “The law brings wrath” [Rom. 4:15]. How, then, could there be any possibility of attaining righteousness through the law?" [LW 33:271]. Or as he states elsewhere,
The Law cannot restore the soul, for it is a Word that makes demands on us and commands us that we shall love God with all our hearts, etc., and our neighbors as ourselves (Matt. 22:37, 39). It damns him that does otherwise and pronounces this sentence upon him (Gal. 3:10; Deut. 27:26): “Cursed be everyone who does not do all the things written in the Book of the Law.” Now, it is certain that nobody on earth does that; therefore the Law comes in due time with its sentence and only grieves and frightens the souls. Where no help is provided, it presses them so that they must despair and be lost forever. St. Paul therefore says (Rom. 3:20): “By the Law comes only knowledge of sin,” and (Rom. 4:15): “The Law brings only wrath” [LW 12:164]. I would certainly be interested in any Roman Catholic explaining why the way Luther rendered the verse changes its sense (as Father O'Hare argues). In the context of Romans 4, the Law certainly is bringing only wrath. Perhaps it's because Father O'Hare believed the works of the law aid justification. If that's the case, Luther responds:
Paul excludes all works so completely as to say that the works of the Law, though it is God's law and word, do not aid us in justification. Using Abraham as an example, he argues that Abraham was so justified without works that even the highest work, which had been commanded by God, over and above all others, namely circumcision, did not aid him in justification. Rather, Abraham was justified without circumcision and without any works, but by faith, as he says in Chapter 4: "If Abraham were justified by works, he may boast, but not before God." So, when all works are so completely rejected — which must mean faith alone justifies — whoever would speak plainly and clearly about this rejection of works will have to say "Faith alone justifies and not works." The matter itself and the nature of language requires it.
"But," they say, "it has an objectionable tone, and people infer from it that they need not do any good works." Dear me, what are we to say? Is it not much more offensive when Paul himself, while not using the term "faith alone," spells it out even more bluntly, putting the finishing touches on it by saying "Without the works of the Law?" And in Galatians 1 (as well as in many other places) he says "not by works of the law." The expression "faith alone" may perhaps be glossed over somehow, but the phrase "without the works of the law" is so blunt, offensive, and scandalous that no amount of interpretation can help it. How much more might people learn from this that "they need not do any good works," when they hear this teaching about the works themselves stated in such a clear strong way: "No works", "without works", "not by works"! If it is not offensive to preach "without works," "not by works," "no works," why is it offensive to preach "by faith alone"?
Still more offensive is that Paul does not reject just ordinary works, but works of the law! One could easily take offense at that all the more and say that the law is condemned and cursed before God, and so we should be doing nothing but what is against the law, as it is said in Romans 3: "Why not do evil so that there might be more good?" This is what one Rottengeist of our time began to do. Should we reject Paul's word because of such "offense" or refrain from speaking freely about faith? Dear me, Saint Paul and I want to offend like this, for we preach so strongly against works and insist upon faith alone just so that people will be offended, stumble and fall, that they may learn that they are not saved by good works but only by Christ's death and resurrection. Knowing that they cannot be saved by their good works of the law, how much more will they realize that they shall not be saved by bad works, or without the law! Therefore, it does not follow that because good works do not help, bad works will; just as it does not follow that because the sun cannot help a blind man to see, the night and darkness must help him to see.
I am amazed that anyone can object to something as evident as this. Just tell me: Is Christ's death and resurrection our work, that we do, or not? Of course it is not our work, nor is it the work of any law. Now it is Christ's death and resurrection alone which saves and frees us from sin, as Paul writes in Romans 4: "He died for our sins and rose for our justification." Tell me, further: What is the work by which we take hold of Christ's death and resurrection? It cannot be any external work, but only the eternal faith that is in the heart. Faith alone, indeed all alone, without any works, takes hold of this death and resurrection when it is preached through the gospel. Then why all this ranting and raving, this making of heretics and burning them at the stake, when it is clear at its very core that faith alone takes hold of Christ's death and resurrection, without any works, and that his death and resurrection are our life and righteousness? As this fact is so obvious, that faith alone conveys, grasps, and imparts this life and righteousness — why should we not say so? It is not heretical to believe that faith alone lays hold on Christ and gives life; and yet it seems to be heresy if someone mentions it. Are they not insane, foolish and absurd? They will admit that it is right but they brand the telling of it as wrong, though nothing can be simultaneously right and wrong.
Is your assertion that the "law", in Paul's use of it in Romans, does not bring the wrath of God? Perhaps you need to dust off your Bible and read the whole book of Romans.
“This presumably was to attempt to justify his position to discredit the law.”
So if Luther was on FR, you would be mind reading?