In this selection from his sermon on 1 Corinthians 5:6–8, Luther encourages all Christians to resist temptation. Can we do this by ourselves? Certainly not. But God gives His Holy Spirit to us Christians as we interact with His Word and participate in the Sacraments to strengthen our faith and aid us in resisting the devil’s lures.
[H]e shows here . . . the distinction between the saints and the unholy, for both have sin. . . . The sin which remains in the saints is all kinds of evil inclinations and lusts or desires which are active in people against God’s command, which the saints feel just as much as others do. But the difference is that the saints do not let themselves be overcome by them, following them and letting them be carried out. Instead, they oppose them and (as St. Paul says here) always sweep them out. He says that these sins are the ones which are swept out, but the others do not do that; they follow their lusts and give free rein to the flesh, and thus sin against their conscience.
For that reason a good conscience and faith remain in those who oppose their sinful lusts. A good conscience and faith cannot remain in the others who do not oppose sin but follow it, and thus their conscience is offended, and their faith is overthrown. If you remain in your evil intentions and your own conscience testifies against you, then you cannot believe or say that God is gracious to you. For that reason, it is necessary that a Christian not give way to such sinful lusts.
Just for that reason the Holy Spirit is given, so that He would contend against sins and not let them prevail, as St. Paul says, “The Spirit has desires against the flesh, and the flesh against the Spirit,” to which he adds the rule: “so that you do not do what you want to do” (Galatians 5 [:17]). And he writes: “If by the Spirit you put to death the deeds of the flesh, you will live” (Romans 8 [:13]). Likewise: “Let not sin reign in your mortal body, so that you would follow its lusts” (Romans 6 [:12]).
For we also have an Easter Lamb, which is Christ, sacrificed for us. [1 Cor. 5:7]
Here he gives the reason that he said, “You are unleavened.” He says: “You are a new unleavened or sweet dough—not from yourselves or because of your holiness and worthiness, but because you have Christ and believe on Him as the Easter Lamb sacrificed for you. He makes you pure and holy before God, so that you are no longer old yeast, as you were previously apart from and without Christ, but through this sacrifice you have been reconciled to God and cleansed from sin,” etc.
Amended from Luther’s Works volume 77, pages 18–19. © 2014 Concordia Publishing House. All rights reserved.
Take a deeper look at Luther's writings on the Gospels.