I was sent a link to a website "exposing" Calvinism because it contained a bunch of Luther quotes. Many of the quotes I've gone over already, but there were a few that I've never examined. Here's one in particular found in a pdf e-book (pictured left) from this site:
On Predestination“You must say my sins are not mine; they are not in me at all; they are the sins of another, they are Christ's and are none of my business.” 
The reference link is to Peter Wiener's, Martin Luther, Hitler's Spiritual Ancestor. I've gone through a number of Wiener's quotes over the years. Wiener states:
Since Luther had this curious idea that our actions have no connections whatsoever with our thoughts, and that as long as we think in a Christian way, we need not behave accordingly, it is not surprising that he did not hesitate to authorize the commitment of sins. “What does it matter whether we commit a fresh sin?” he asks sarcastically. “Faith cancels all sin” is his simple counsel. “No other sin exists in the world save unbelief,” is his doctrine. Indeed, his old enemy, Satan, is once more coming to light in order to give an excuse to sinners. “Sometimes it is necessary to commit some sin out of hatred and contempt for the Devil.” “What matters if we commit a sin?” (E16, 254).
But then again, he sometimes consoles himself with the thought that it was God who ordained sins. “You must say my sins are not mine; they are not in me at all; they are the sins of another' they are Christ's and are none of my business” (W25, 330). “What a consolation for pious souls to put Him on like this and wrap Him in my sins, your sins, the sins of the whole universe, and consider Him thus bearing all our sins.” “Christianity is nothing but a continual exercise in feeling that you have no sin although you sin, but that your sins are thrown on Christ.” “From the moment when you acknowledge that Christ bears your sins, He becomes the sinner in your stead.”It's probable Wiener took this quote from the work of Roman Catholic historian Hartmann Grisar:
"He lives in a different world," says Luther, "where he must know nothing either of sin or of merit; if however he feels his sin he is to look at it as clinging, not to his own person, but to the person (Christ) on whom God has cast it, i.e. he must regard it, not as it is in itself and appears to his conscience, but rather in Christ by Whom it has been atoned for and vanquished. Thus he has a heart cleansed from all sin by the faith which affirms that sin has been conquered and overthrown by Christ. . . . Hence it is sacrilege to look at the sin in your heart, for it is the devil who puts it there, not God. You must say, my sins are not mine; they are not in me at all; they are the sins of another; they are Christ's and are none of my business." Elsewhere he describes similarly the firm consolation of the righteous with regard to the Law and its accusations of sin: "This is the supreme comfort of the righteous, to vest and clothe Christ with my sins and yours and those of the whole world, and then to look upon Him as the bearer of all our sins. The man who thus regards Him will soon come to scorn the fanatical notions of the sophists concerning justification by works. They rave of a faith that works by love ('fides formata caritate'), and assert that thereby sins are taken away and men justified. But this simply means to undress Christ, to strip Him of sin, to make Him innocent, to burden and load ourselves with our own sins and to see them, not in Christ, but in ourselves, which is the same thing as to put away Christ and say He is superfluous.''WA 25:330 can be found here. This quote is from Luther's material on Isaiah 53. Some of the material is found in WA 31(2), some of it is found in WA 25 (pp. 79-401). The material in WA 31 comprises of lectures transcribed and recorded by those who heard Luther give these lectures. The material in WA 25 comprises of scholia. Therefore, taken together, Luther's notes and lectures comprise his material on the book of Isaiah. LW chose to translate the material from WA 31 with clarification from Luther's scholia ("... there is neither need nor even justification for relying on the scholia, and we have decided to translate the version closest to Luther himself").
If one compares the scholia and the lectures on Isaiah 53 there is indeed harmony in thought. Note the context from Luther's lectures on Isaiah 53:
4. Surely He has borne our griefs and carried our sorrows; yet we esteemed Him stricken, smitten by God, and afflicted.
This states the purpose of Christ’s suffering. It was not for Himself and His own sins, but for our sins and griefs. He bore what we should have suffered. Here you see the fountain from which St. Paul draws countless streams of the suffering and merits of Christ, and he condemns all religions, merits, and endeavors in the whole world through which men seek salvation. Note the countless sects who to this day are toiling to obtain salvation. But here the prophet says, “He for us.” It is difficult for the flesh to repudiate all its resources, to turn away from self, and to be carried over to Christ. It is for us who have merited nothing not to have regard for our merits but simply to cling to the Word between heaven and earth, even though we do not feel it. Unless we have been instructed by God, we will not understand this. Therefore I delight in this text as if it were a text of the New Testament. This new teaching which demolishes the righteousness of the Law clearly appeared absurd to the Jews. For that reason the apostles needed Scripture, Surely He has borne our griefs. His suffering was nothing else than our sin. These words, OUR, US, FOR US, must be written in letters of gold. He who does not believe this is not a Christian. Yet we esteemed Him. We thought that He was suffering because of His own sin, as it were. In the eyes of the world and of the flesh Christ does not suffer for us, since He seemed to have deserved it Himself. This is what the prophet says here too, that He was judged guilty in the eyes of the world. It is therefore difficult to believe that such a one suffered for us. The Law is that everybody dies for his own sins. Natural reason, and divine as well, argues that everybody must bear his own sin. Yet He is struck down contrary to all law and custom. Hence reason infers that He was smitten by God for His own sake. Therefore the prophet leads us so earnestly beyond all righteousness and our rational capacity and confronts us with the suffering of Christ to impress upon us that all that Christ has is mine. This is the preaching of the whole Gospel, to show us that Christ suffered for our sake contrary to law, right, and custom. He expounds more fully what His suffering for us means.
5. He was wounded.
The prophet is eloquent in describing the suffering of Christ. Word by word he expounds it in opposition to the hardened Jews. Do you want to know what it is to bear our sins, that is, what it means that He was wounded? Here you have Christ delineated perfectly and absolutely, since this chapter speaks of Him. Christ is a man, a servant of the Word, who by means of suffering bore our sins. What will the unrestrained Jew answer in opposition to this delineation? From this you must infer how far apart are the teachings of Paul and the pope. Paul clings to Christ alone as the sin bearer. By means of this one word, “Lamb of God” (John 1:29), John the Baptist understands this Levitical sacrifice, that He suffered for the sins of all. It follows, then, that the Law and merits do not justify. Away with the Antichrist pope with his traditions, since Christ has borne all these things! I marvel that this text was so greatly obscured in the church. They note the concern of Scripture that faith without works is dead, and we say the same thing. In public argument, however, we say that works are indeed necessary, but not as justifying elements. Thus anyone may privately come to the conclusion, “It is all the same whether I have sinned or whether I have done well.” This is hard for the conscience to believe, that it is the same and in fact something angelic and divine. Therefore this text draws the following conclusion: “Christ alone bears our sins. Our works are not Christ. Therefore there is no righteousness of works.” Surely none of the papists can escape this fact when he sees Scripture as a whole, that Christ has accomplished all things for justification and therefore we have not done it. Appeal to works, rewards, and merits and make much of them in the realm of outward recompense. Only do not make them responsible for justification and the forgiveness of sins. We can preach and uphold this passage in public, but we can only believe it with difficulty in private. If we preserve this article, “Jesus Christ is the Savior,” all other articles concerning the Holy Spirit and of the church and of Scripture are safe. Thus Satan attacks no article so much as this one. He alone is a Christian who believes that Christ labors for us and that He is the Lamb of God slain for our sins. While this article stands, all the monasteries of righteousness, etc., are struck down by lightning. In the light of this text read all the epistles of Paul with regard to redemption, salvation, and liberation, because they are all drawn from this fountain. A blind papacy read and chanted these and similar words as in a dream, and no one really considered them. If they had, they would have cast off all righteousness from themselves. Hence it is not enough to know and accept the fact. One must also accept the function and the power of the fact. If we have this, we stand unconquered on the royal road, and the Holy Spirit is present in the face of all sects and deceptions. When this doctrine is safe, we firmly stand up to all people, but where this article is lost, we proceed from one error to the next, as we observe in the babbling Enthusiasts and in Erasmus. Our nature is opposed to the function and power of Christ’s Passion. As far as the fact itself is concerned, both the pope and the Turk believe it and proclaim it, but they do not accept its function. As for you, lift up this article and extol it above every law and righteousness and let it be to you a measureless sea over against a little spark. The sea is Christ who has suffered. Your works and your righteousness are the little spark. Therefore beware, as you place your sins on your conscience, that you do not panic, but freely place them on Christ, as this text says, “He has borne our iniquities.” We must clearly transfer our sins from ourselves to Christ. If you want to regard your sin as resting on you, such a thought in your heart is not of God but of Satan himself, contrary to Scripture, which by God’s will places your sin on Christ. Hence you must say: “I see my sin in Christ, therefore my sin is not mine but another’s. I see it in Christ.” It is a great thing to say confidently: “My sin is not mine.” However, it is a supreme conflict with a most powerful beast, which here becomes most powerful: “I behold sins heaped on Christ.” Thus a certain hermit who was extremely harassed by Satan could not evade him, but said: “I have not sinned. Everybody must look upon his conscience as free.” He did not answer well because he did have sin. This is what he should have said: “My sins have been transferred to Christ; He has them.” This is the grafting of the wild olive into the olive tree. It is not without purpose that the prophet uses so many words in this article, since it is necessary for a Christian to know that these are his own sins, whatever they are, and that they have been borne by Christ, by whom we have been redeemed and saved. This is the Savior, etc., from eternal damnation, from death, and from sin. So by this thunderbolt the Law and its righteousness are struck down, as you see Paul treat this matter in detail..[LW 17:221-225]Conclusion
What I find fascinating about this particular quote is the way it's interpreted three different ways. The website under scrutiny above uses it in regard to predestination. Peter Wiener thinks it means that since Christ has bore our sins, one "need not behave accordingly" and that God "ordained sins." Grisar comes closest to the actual correct understanding of the context, but his Latin translation makes it look as though Satan puts all sin in the heart, where the context shows it's the thought of regarding "sin as resting on you" that Satan places in the heart (Perhaps though this was simply something lost when Grisar was translated from German to English). This is a good example of why a context is so important!