Martin Luther is considered the initiator of the Reformation, beginning when he nailed the Ninety Five Theses on the door of the Wittenberg Church for public discussion. In this document he criticized the roman church for many of its practices, including the sale of indulgences, in which someone could pay money to the church to obtain forgiveness of sins. He was eventually tried for his beliefs and excommunicated. His followers became known as "Protestants." He is best known for the following theological contributions:
1. Total inability of man. In On the Bondage of the Will, Luther argues that man is so corrupted by the Fall that he is unable to do anything good on his own, without divine help. He refutes the humanistic ideas of Erasmus, and defends God's sovereignty and grace.
2. Justification by faith. Luther himself had struggled to find peace with God, and had discovered the doctrine of justification by faith in passages such as Romans 1:17 and Ephesians 2:8-10. For Luther, justification was not a process of becoming more holy, but an act of God in which He declared a person legally righteous through faith in Christ. Even saving faith is a gift of God. Salvation is not by any merit of man, but only by the grace of God. (See On the Bondage of the Will.)
3. Rejection of the papacy. In On the Babylonian Captivity of the Church, Luther rejects the authority of the pope and defends the principle that all believers are priests.
