“Christ is God and man in one person. He has neither sinned nor died, and is not condemned, and He cannot sin, die, or be condemned; His righteousness, life, and salvation are unconquerable, eternal, omnipotent.
By the wedding ring of faith He shares in the sins, death, and pains of hell which are His bride’s. As a matter of fact, He makes them His own and acts as if they were His own and as if He Himself had sinned; He suffered, died, and descended into hell that He might overcome them all.
Now since it was such a one who did all this, and death and hell could not swallow Him up, these were necessarily swallowed up by Him in a mighty duel; for His righteousness is greater than the sins of all men, His life stronger than death, His salvation more invincible than hell.
Thus the believing soul by means of the pledge of its faith is free in Christ, its bridegroom, free from all sins, secure against death and hell, and is endowed with the eternal righteousness, life, and salvation of Christ its bridegroom.
So He takes to himself a glorious bride, “without spot or wrinkle, cleansing her by the washing of water with the word” (Eph. 5:26–27) of life, that is, by faith in the Word of life, righteousness, and salvation. In this way He marries her in faith, steadfast love, and in mercies, righteousness, and justice, as Hos. 2:19–20 says.
Who then can fully appreciate what this royal marriage means? Who can understand the riches of the glory of this grace?
Here this rich and divine bridegroom Christ marries this poor, wicked harlot, redeems her from all her evil, and adorns her with all His goodness. Her sins cannot now destroy her, since they are laid upon Christ and swallowed up by Him.
And she has that righteousness in Christ, her husband, of which she may boast as of her own and which she can confidently display alongside her sins in the face of death and hell and say, “If I have sinned, yet my Christ, in whom I believe, has not sinned, and all His is mine and all mine is His,” as the bride in the Song of Solomon 2:16 says, “My beloved is mine and I am his.”
This is what Paul means when he says in 1 Cor. 15:57, “Thanks be to God, who gives us the victory through our Lord Jesus Christ,” that is, the victory over sin and death, as he also says there, “The sting of death is sin, and the power of sin is the law” (1 Cor. 15:56).”
–Martin Luther, The Freedom of the Christian (1520), in Luther’s Works, Vol. 31: Career of the Reformer I (ed. Jaroslav Jan Pelikan, Hilton C. Oswald, and Helmut T. Lehmann; vol. 31; Philadelphia: Fortress Press, 1999), 31: 351–352.