The reasons Martin Luther criticized the Catholic Church are:
- The sale of indulgences by Church officials.
- The accumulation of wealth by Church officials.
Martin Luther was a theologian and a Catholic monk known for the Catholic reform that led to the Protestant reform, his movement was known as Lutheranism. He advocated various reforms of the Catholic Church criticizing certain practices such as the sale of indulgences.
The indulgences were documents that freed from guilt or sins to any living or dead person who had committed it, they were basically a pardon for people to enter heaven.
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