Even in his youth in 1510, Martin Luther, a learned Catholic monk and a man of lively conscience, saw the extreme depravity of the papal court and the clergy of Rome. This strongly influenced him to change his theological convictions and shook his former view of the holiness of priests in the Roman Catholic Church.

In 1516 he observed how for the sake of obtaining funds to build St. Peter’s Cathedral in Rome, the Catholics widely sold “indulgences,” i.e. absolution not only of past sins, but also of future ones! Luther publicly condemned such a blasphemous trade. He explained to his adepts that deliverance from punishment for sins may be obtained only through inner repentance. A verbal duel sprang up between Luther and Tetzel, a learned Dominican monk, who threatened Luther with excommunication and hinted at his right to burn heretics. In response, in 1517 Luther hammered to the door of the Wittenberg church his 95 theses, in which he stated his views on repentance, justification by faith, and the harm of selling indulgences. The debate continued for several years, during which Luther rejected the authority of the Pope, while the Pope excommunicated Luther from the church. Only the intercession of civil authorities saved Luther from death. He was supported in Germany by many priests, professors, students, knights and princes. A schism with Rome began, and Luther and his followers separated from the Roman Catholic Church.

The movement for cleansing the Church of papal inventions and abuses did not stop with Germany. Zwingli and Calvin, continuing with church reforms, went farther than Luther in their teachings on morality and the sacraments. The main feature of Calvin’s teaching became the teaching on pre-determination, according to which God has from the very beginning pre-determined some people for salvation and others for perdition. This teaching basically negates the need for Christian spiritual labors and good deeds.