Martin Luther (10 November 1483 – 18 February 1546) was a German monk, priest, professor of theology and iconic figure of the Protestant Reformation. He strongly disputed the claim that freedom from God's punishment for sin could be purchased with money. He confronted indulgence salesman Johann Tetzel with his Ninety-Five Theses in 1517. His theology challenged the authority and office of the Pope by teaching that the Bible is the only source of divinely revealed knowledge from God.
On October 31, 1517. Martin Luther, a 33-year-old theology professor at Wittenberg University walked over to the Castle Church in Wittenberg and nailed a paper of 95 theses to the door, hoping to spark an academic discussion about their contents. It became a key event in igniting the Reformation.