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Restate
The Reformation was the result of the discontent with the Catholic Church due to corrupt practices that sold indulgencies, according to the church reformers.
Answer
The cause of the schism between the Roman Catholic and Protestant branches of Christianity was Martin Luther’s "95 Theses." And important medieval document that fueled the Protestant Reformation. This document criticized the corruptive practices of the Roman Catholic Church, including the selling of indulgences.
Martin Luther (1483-1546) was a German Theologian that was the most important figure in the Protestant Reformation of the Church. His ideas changed Christianity and led to the separation of the Catholic Church. Luther questioned the main principles of Catholicism. He wrote the document called "95 Thesis" or "Disputation on the Power of Indulgencies," where he critiques the selling of plenary indulgences to forgive sins.