Final answer:
Martin Luther, a German monk, challenged the Church in 1517, criticizing practices like the selling of indulgences and the use of Latin in Mass. This sparked his creation of the Ninety-five Theses, and eventually led to his excommunication. However, despite his excommunication, Luther's teachings became a catalyst for the Protestant Reformation.
Step-by-step explanation:
The German monk who questioned the Church in 1517 is known as Martin Luther. He was a critic of the Catholic Church’s practices, such as the indiscriminate selling of indulgences, ecclesiastical taxation, and the use of Latin in services which wasn’t understood by the common German folks. This led to him drafting the Ninety-five Theses, directly challenging the church’s actions.
Despite probably wishing to simply reform the church and not instigate rebellion, Luther’s actions were seen as defiance against the church. In 1518, church authorities summoned him to answer for his beliefs, to which he outright denied the church's power in distributing merits achieved by Jesus and the saints. When he was ordered to recant and refused, he was excommunicated.
Luther’s actions resulted in the beginning of the Protestant Reformation. His teachings were groundbreaking for the time such as preaching that faith alone was needed for salvation and scripture was the ultimate source of Christian authority.
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