Why was Martin Luther's ideas so provocative?

For fifteen centuries, the Church had taught Christianity, excommunicated heretics, and shepherded the Christian faithful throughout life. Martin Luther was an Augustinian friar who was under voluntary obedience to his religious superiors, and voluntary obedience to his Bishop, he was also under religious vows, which he had taken as an adult, after years of reflection, before God in Church. He left his Friary, left his Order, denied his priesthood, denied his religious heritage and led other people out of the Church and opposed the religious authorities and the Holy Father in Rome. His language is not fit to be repeated, Martin Luther was a coarse, irreverent, man who broke all of his vows, publicly ridiculed the authorities, and hid. He then proceeded to make up his own religion from scratch.