Final answer:
Martin Luther criticized the Catholic Church's practice of selling indulgences, believing that only God could grant forgiveness. He also opposed the idea that the pope had control over purgatory. His objections resulted in the creation of the Ninety-five Theses and ultimately led to the Protestant Reformation.
Step-by-step explanation:
Martin Luther, a German Catholic monk, was famously critical of the Roman Catholic Church's practice of selling indulgences, documents that were thought to absolve sinners of their transgressions. This practice was objectionable to Luther because he believed that only God could grant forgiveness and that humans could do nothing to ensure their salvation, a belief known as the doctrine of justification by faith.
Additionally, Luther argued that the pope had no control over purgatory and rejected the concept that merit amassed by Jesus and the saints could be allocated to others. He was alarmed that sinners might be led to believe they could access heaven through the purchase of an indulgence, rather than through sincere repentance or God's mercy.
Luther crafted ninety-five arguments against the sale of indulgences in a document called the Ninety-five Theses, intending to incite discussion and reform within the Church. Despite his intentions, Luther was eventually excommunicated and his ideas spurred the Protestant Reformation, a significant religious movement that championed faith alone as the path to salvation and the scripture as the sole authority of Christian belief.
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