According to tradition, on October 31, 1517, Martin Luther posted 95 theses in Latin on a poster at this door in order to debate them with scholars. The debate was intended to clarify whether the church's trade in "indulgences" corresponded to what Jesus once wanted. That was the beginning of the Reformation. The old wooden "theses door" was lost in the great fire of the church in 1760. In 1858, the Prussian King Frederick William IV donated the current bronze door, in the wings of which the Latin theses are cast.

 Content of the theses in detail
1: When our Lord and Master Jesus Christ says "Repent" etc. (Matt. 4:17), he wanted the whole life of the faithful to be penance.[1]
2: This word cannot be understood in reference to penance as a sacrament - that is, confession and satisfaction - administered by the priestly office.[1]
3: It does not refer only to an inner penance, indeed such a penance would not be one at all if it did not bring about various external works to mortify the flesh.[1]
4: Therefore, the punishment remains as long as the hatred of oneself - that is, true penance of the heart - remains, that is, until one enters the kingdom of heaven.[1]
5–6: The Pope can only remit punishments that he himself has imposed. 7: God only remits punishments to those who submit to the Pope (God's representative on earth).
8–9: The church's regulations on penance and remission of punishments only apply to the living, not to the dead.
10–13: A punishment may not be pronounced for the time after death.
14: The less faith in God, the greater the fear of death.
15–16: This fear alone characterizes purgatory as a place of purification from heaven and hell.
17–19: It is certain that the deceased in purgatory can no longer change their relationship with God.
20–24: The indulgence preachers are wrong when they say: "Every punishment is remitted."
25: The same power that the Pope has with regard to purgatory in general is possessed by every bishop and every pastor in his area of ​​work. 26–29: The Pope obtains forgiveness in purgatory through intercession, but the indulgence preachers are wrong when they promise forgiveness in exchange for money. In this way, the Church's income increases, but intercession depends solely on God's will.
30–32: No one can obtain forgiveness with certainty through indulgences.
33–34: The Pope's indulgence is not a gift from God through which people are reconciled with God, but only a forgiveness of the punishments imposed by the Church.
35–40: No one can receive forgiveness without repentance; but those who truly repent are entitled to complete forgiveness - even without paying for an indulgence.
41–44: Buying indulgences has nothing to do with charity, and it only partially exempts one from punishment. More important are good works of charity such as supporting the poor or those in need.
45–49: Anyone who does not help a needy person but instead buys indulgences will incur the wrath of God.
50–51: If the Pope knew the blackmail methods of indulgence preachers, he would not have St. Peter's Basilica built in Rome.
52–55: No salvation can be expected from an indulgence letter. It is wrong for a sermon to spend more time talking about indulgences than about God's word.
56–62: The treasure of the Church from which the Pope distributes indulgences does not consist of worldly goods, but of the Gospel. But the forgiveness of sins through Jesus Christ is the true treasure of the Church.
63–68: Indulgences are the net with which the wealth of the wealthy is now caught.
69–74: Bishops and priests should watch indulgence preachers so that they do not preach their own opinions instead of the Pope's. 71–74: Anyone who speaks against the truth of the apostolic indulgence is to be rejected and cursed. The Pope wants to hurl the anathema against those who, under the pretext of indulgences, plan to deceive holy love and truth.
75–76: Indulgences cannot forgive serious or even minor sins.
77–78: The Pope can receive abilities from God, just like the Apostle Simon Peter, as is written in 1 Cor 12:1-11 EU.
79–81: It is blasphemy to equate the indulgence cross with the coat of arms of the Pope in churches with the cross of Jesus Christ. Anyone who preaches such a cheeky sermon can endanger the Pope's reputation, for example by asking subtle questions from laypeople:
82: Why doesn't the Pope abolish purgatory for everyone?
83: Why do funeral masses for the dead continue to exist if it is not permitted to pray for those who have been redeemed?
84: Why can an ungodly person forgive sins for money?
85: Why are the penitential statutes, which have practically been abolished, still paid for with money?
86: Why does the rich Pope not at least build St. Peter's Basilica with his money?
87: What does the Pope forgive someone who, through complete repentance, is entitled to complete remission of sins?
88: Why does he only grant forgiveness to all believers once a day and not a hundred times a day?
89: Why does the Pope revoke previous indulgences?
90–93: If indulgences were preached according to the Pope's views, these objections would disappear. So away with these false indulgence preachers. 94–95: Christians should be encouraged to follow Jesus Christ and not allowed to buy false spiritual security through indulgences.

Summary
The document follows the style of disputation theses, as was common at the time for academic doctorates, and is written in Latin. Starting with Jesus' words "Repent" (Mt 4:17 LUT), Luther initially turns against the fear of purgatory stoked by the church. From thesis no. 21 onwards, the focus of his remarks is on the sale of indulgences. He describes indulgences as "good business" (no. 67), but denies them any power to "take away even the smallest venial sin" (no. 76). No. 81 announces "subtle questions from the laity" which turn out to be rhetorical questions, for example No. 86: "Why does the Pope, who is today richer than the richest Crassus, not build at least one church, St. Peter's, with his own money rather than that of the poor believers?" The conclusion is an appeal to Christians "to strive to follow their head, Christ, through punishment, death and hell, and to trust that they will enter the kingdom of heaven through many tribulations rather than to rest in false spiritual security."