From today's Writer's Almanac:
On this date in 1512, Martin Luther joined the faculty of the University of Wittenberg. As a young man, Luther planned to study the law, but when he was caught in a powerful storm in 1505, he vowed to St. Anne that he would become a monk if he lived through the storm. He didn't feel fulfilled by his experience in the monastery, and his disillusionment only grew after he was made a delegate to a church conference in Rome. When he got back to Germany, he decided to pursue his doctorate at the University of Wittenberg. He did so well that he was asked to teach there as a professor of theology. The act of preparing lessons for his students led him to think more deeply about his own faith, and what it was that bothered him about the Roman Catholic Church. In 1517, Pope Leo X announced the sale of indulgences to help finance the construction of St. Peter's Basilica. People could give money to the church to lessen their punishment for their sins. Luther was enraged and wrote a document called "Disputation on the Power of Indulgences" — commonly known as "the Ninety-five Theses" — explaining why the sale of indulgences corrupted people's faith. He nailed his theses to the door of the university chapel, and kicked off the Protestant Reformation.
Not long ago, we read the excellent "Leaving the Witness", in which author Amber Scorah recites her story of deep feeling for her religion, her facility in learning languages, being sent to China as a more or less secret missionary and what happened. She reports that translating her religious message into another language repeatedly caused her to think and re-think the ideas and led to deep doubts and new convictions.