From the Word
19 On the evening of that day, the first day of the week, the doors being shut where the disciples were, for fear of the Jews, Jesus came and stood among them and said to them, “Peace be with you.” 20 When he had said this, he showed them his hands and his side. Then the disciples were glad when they saw the Lord. 21 Jesus said to them again, “Peace be with you. As the Father has sent me, even so I send you.” 22 And when he had said this, he breathed on them, and said to them, “Receive the Holy Spirit. 23 If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained.”
John 20:19–23, RSV
This is a great and mighty power which no one can sufficiently extol, given to mortal men of flesh and blood over sin, death, hell and all things. The pope, too, boasts in the canon law, that Christ has given him power over all earthly things; which indeed is correct if the people rightly understood it. They apply it to the civil government; this is not Christ’s thought; he wishes to say that when ye speak a word concerning a sinner it shall be spoken in heaven and shall avail as much as if God himself had spoken it. This is not civil, but spiritual power.
If Christ speaks a word, it must be so, since he is Lord over sin and death. When he says to you: Thy sins are forgiven, they must be forgiven and nothing can prevent it. If he says: Thy sins shall not be forgiven thee, they remain unforgiven, so that neither you, nor an angel, nor a saint, nor any creature, can forgive your sin, even if you tortured yourself to death. But in this matter one must not do like the popes. They have reached the point to claim the power that whatever they say, so it must be. If the pope says: Thy sins are forgiven thee, they are blotted out, even though you do not repent, nor believe. They mean by this that they have the power to open or shut heaven. From this it would follow that our salvation depended upon the authority and power of man. Since this is in conflict with all the Scriptures, it cannot be true. These words do not establish the power of him who speaks, but of him who believes. God has given us the Word and authority to speak. This power belongs to every Christian, since Christ has made us all partakers of his power and dominion. Here is not a civil but a spiritual rule, and Christ’s followers rule spiritually. Christ’s meaning is: Ye shall have the power to speak the Word, and to preach the gospel, and whosoever believeth has the remission of his sins; but whosoever believeth not has no remission of sin. Therefore if you believe the Word, you gain this power; but if you believe not, then what I speak or preach will avail nothing even though it be God’s Word.
Luther, Martin, and John Sander. Devotional Readings from Luther’s Works for Every Day of the Year. Augustana Book Concern, 1915, pp. 344–45.