This year marks 500 years since German monk Martin Luther nailed 95 theses to a church door in the German city of Wittenberg, sparking the Protestant Reformation.
On Sunday, Oct. 29, churches across the nation celebrate Reformation Sunday in honor of the anniversary of Luther's action.
Luther's theses, or points of debate, argued against various practices of the Roman Catholic Church and addressed matters regarding salvation and works.
A big focus was on the indulgences, a common practice at the time which involved giving something, oftentimes money, to the Church in return for receiving forgiveness.
Here are 12 memorable statements from one of the most important and history-changing documents in western civilization.
"The pope neither desires nor is able to remit any penalties except those imposed by his own authority or that of the canons."
"God remits guilt to no one unless at the same time he humbles him in all things and makes him submissive to the vicar, the priest."
"The penitential canons are imposed only on the living, and, according to the canons themselves, nothing should be imposed on the dying."
"Those who believe that they can be certain of their salvation because they have indulgence letters will be eternally damned, together with their teachers."
"Christians are to be taught that he who gives to the poor or lends to the needy does a better deed than he who buys indulgences."
"Christians are to be taught that he who sees a needy man and passes him by, yet gives his money for indulgences, does not buy papal indulgences but God's wrath."
"The true treasure of the church is the most holy gospel of the glory and grace of God."
"To consider papal indulgences so great that they could absolve a man even if he had done the impossible and had violated the mother of God is madness."
"Why does not the pope empty purgatory for the sake of holy love and the dire need of the souls that are there if he redeems an infinite number of souls for the sake of miserable money with which to build a church?"
"Why does not the pope, whose wealth is today greater than the wealth of the richest Crassus, build this one basilica of St. Peter with his own money rather than with the money of poor believers?"
"What greater blessing could come to the church than if the pope were to bestow these remissions and blessings on every believer a hundred times a day, as he now does but once?"
"To repress these very sharp arguments of the laity by force alone, and not to resolve them by giving reasons, is to expose the church and the pope to the ridicule of their enemies and to make Christians unhappy."