What role did Martin Luther play in the Reformation?

Martin Luther's pivotal role in the Reformation is widely recognized for his act of nailing the Ninety-Five Theses to the door of the Wittenberg Castle Church in 1517. This document outlined various criticisms of the Catholic Church, particularly against the sale of indulgences, which were seen as a corrupt practice that undermined genuine repentance. By publicly posting his theses, Luther initiated a vigorous debate over church practices and doctrine, which resonated throughout Europe.

This act is considered the catalyst for the Protestant Reformation, leading to significant theological shifts, the emergence of various Protestant denominations, and ultimately a fundamental transformation of the Christian faith as it was practiced at that time. Luther not only questioned the authority of the Pope and the Church hierarchy but also argued for justification by faith alone, which became a key tenet of Protestant theology.

In contrast, the other options do not accurately represent Luther's contributions. He did not lead military campaigns, compose an official Protestant Bible (though he translated the Bible into German, making it more accessible), or establish the first Protestant church in England. These activities were part of broader Reformation movements that involved many other figures and developments. Luther’s singular act of posting the Ninety-Five Theses is what truly