Short answers, pulled from the story.
Martin Luther was a German priest, theologian, author, hymnwriter, professor, and former Augustinian friar who lived from 1483 to 1546. He was the seminal figure of the Protestant Reformation, and his theological beliefs form the basis of Lutheranism.
Martin Luther's Ninety-five Theses, written in 1517, were a disputation protesting the sale of indulgences, which Johann Tetzel was selling in Germany to fund the rebuilding of St Peter's Basilica in Rome. Luther argued that forgiveness was God's alone to grant, so claims that indulgences wiped away all punishment and secured salvation were in error.
Pope Leo X excommunicated Martin Luther on the 3rd of January 1521 after Luther refused to recant forty-one sentences drawn from his writings within the sixty days demanded by the bull Exsurge Domine. Luther publicly burned that bull in Wittenberg on the 10th of December 1520, and the excommunication was never lifted.
Martin Luther taught that justification, God's act of declaring a sinner righteous, comes by faith alone through God's grace as a free gift, not earned by human acts, intents, or merit. He held that good works were a necessary fruit of living faith rather than the cause of salvation.
At the Diet of Worms, Martin Luther appeared on the 17th of April 1521 before Emperor Charles V and refused to recant his writings, saying his conscience was captive to the Word of God. The Edict of Worms, issued on the 25th of May 1521, declared him an outlaw, banned his literature, and required his arrest.
Martin Luther translated the New Testament into German by 1522 and completed the full Bible by 1534, using the German of the Saxon chancellery so that both northern and southern Germans could read it. His translation fostered a standard version of the German language and influenced other vernacular translations, including the Tyndale Bible, a precursor of the King James Bible.
Martin Luther published On the Jews and Their Lies in 1543, calling Jews "the devil's people" and advocating that synagogues be burned, prayerbooks destroyed, rabbis forbidden to preach, and property seized. Some historians contend his rhetoric encouraged antisemitism in Germany and, centuries later, the emergence of the Nazi Party.