Who is recognized as the herald of reform in Christianity?

The herald of reform in Christianity is widely recognized as Martin Luther. His actions, particularly the posting of the Ninety-Five Theses in 1517, marked a significant turning point in Christian history and initiated what is known as the Protestant Reformation. Luther's criticisms of the Catholic Church, particularly regarding the sale of indulgences and the authority of the Pope, stirred a movement that sought to restore biblical teachings as the foundation of Christianity. His emphasis on justification by faith alone, the priesthood of all believers, and the translation of the Bible into vernacular languages helped to spread reformative ideas and inspire other reformers.

While John Wycliffe, John Calvin, and Ulrich Zwingli also made significant contributions to the reformational movement, their contributions came at different times and contexts. Wycliffe's earlier efforts against church corruption in the 14th century laid the groundwork for later reformers, but Luther's actions are seen as the starting point of this major religious upheaval. Calvin and Zwingli built upon Luther's foundation, each contributing unique theological perspectives and establishing their own branches of reform within Christianity.