By this John means to say: I have, by my teaching, made you all sinners, having condemned your works and told you to despair of yourselves. But in order that you may not also despair of God, I will show you how to get rid of your sins and obtain salvation. Not that you can strip off your sins or make yourselves pious through your works; another man is needed for this; nor can I do it, I can point him out, however. It is Jesus Christ, the Lamb of God. He, he, and no one else in heaven or on earth, takes our sins upon himself. You yourselves could not pay for the very smallest of your sins. He alone must take upon himself not alone your sins, but the sins of the world, and not some sins, but all the sins of the world, be they great or small, many or few.
Now if you are able to believe that this voice of John speaks the truth, and if you are able to follow his finger and recognize the Lamb of God carrying your sins, then you have gained the victory, then you are a Christian, a master of sin, death, hell and all things. Then your conscience will rejoice and become heartily fond of this gentle Lamb of God. Then you will love, praise and give thanks to our heavenly Father for his infinite wealth of mercy, preached by John and given in Christ. Finally you will become cheerful and willing to do his divine will, as best you can, with all your strength. What lovelier and more comforting message can be heard than that our sins are not ours any more, that they no more lie on us, but on the Lamb of God. Lying on him, sin must be vanquished and made to nothing, and likewise death and hell, being the reward of sin, must be vanquished also. Behold what God our Father has given us in Christ.
Take heed lest you presume to get rid of the smallest of your sins through your own merit before God, and lest you rob Christ, the Lamb of God, of his credit. John indeed demands that each one should know himself, repent and grow better, yet not in himself, but in Jesus Christ alone.
With reference to the forgiveness of sins let me say that you will not find anything in your heart with which you can pay them off, nor raise any funds for which God might recognize you and cancel the debt in the ledger. But if you seize Christ as the one who has become your substitute, who has taken your sin upon himself, and who has given himself with all his merit and worthiness for you, no sin can avail anything against you. If I am a sinner, he is holy and Lord over sin, death, Satan and hell, so that no sin can harm me, because he has been given me as my righteousness and salvation.
Through grace we have, indeed, the forgiveness of all sins, but in no way except in and through Christ alone, and in him only it must be sought and can be obtained. Whoever will come before God with any kind of work, which God is to recognize as meritorious for obtaining grace, will be disappointed and deceived, yea, instead of grace he will heap wrath upon himself. All other ways and means are condemned as the doctrines of devils, as when men are led and directed to their own works, or to the holiness and merits of others, as of the saints who have led ascetic lives or have suffered and expiated a great deal; or as those have done who have comforted people in the throes of death by admonishing them to suffer death willingly for their sins. Whoever dares to offer anything else for sin or to atone for it himself does nothing less than deny the Lord Jesus Christ, disgrace and slander him, as if the blood of Christ were of no more consequence than our repentance and satisfaction, or were not sufficient to take away all the sins of the world.
Would you, then, be freed from your sins, you need not chastise yourself with them, nor have anything to do with them, but simply creep under the wings and into the bosom of Christ, as he is the one who has taken them away and has laid them upon himself. Martin Luther