The Reformation began in the 15th-16th centuries as reformers like John Wycliffe, John Huss, and Martin Luther spoke out against corruption and doctrines of the Roman Catholic Church. Wycliffe produced the first English language Bible and taught that salvation could not be revoked. Luther wrote the 95 Theses arguing against indulgences and realized salvation comes through faith alone, not works. The Reformation spread across Europe through reformers like Zwingli and Calvin and led to common Protestant doctrines like sola scriptura and sola fide. In response, the Catholic Church launched the Counter Reformation to combat heresy through means like the Jesuits and Inquisition.