The original purpose of Martin Luther, the father of Reformation, was to get changes and reforms in some of the Catholic Church´s practices and doctrinal issues. His criticism was not intended to make a revolution in religion in Europe; he himself was a priest and a theology professor at a Catholic seminar in Wittenberg in the 1510s. Nevertheless, his theses and calls for changes were rejected by the Vatican and he was even excommunicated by the pope.
Luther particularly critized the sales of papal bulls and indulgences to get forgiveness of sins or reduce purgatoy time of the souls of the dead. This was utterly unacceptable to him. He also blasted the earthly power, riches and privileges of the top church officials. Luther wanted to go back to the original roots of  Christianity, to improve the practice of faith in his times (first half of the 16the century). He stated that salvation is God´s grace and can be achieved only through faith and that the ultimate authority in religious issues is the Bible, not the Vatican´s interpretations. In the end, his goals  were to make Christian practive of faith and worship simpler, more genuine, bring it back to its origins and be guided by the Bible text.
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