Lots of misconceptions of Martin Luther....
1. He wanted to start a new church. Nope. He was not (at all) a revolutionary or reconstructionist (indeed, he powerfully renounced them). I'll admit the language surrounding all this got terrible and very polmemic (which leads to this misunderstanding) but in reality, Luther clearly considered himself Catholic (big "C"), he overwhelmingly agreed with the RCC, he had a great respect for the RCC. Luther was not the revolutionary some secular historians (and some Catholics) try to make him out to be, he was a reformer. There were a few things that needed REFORM. He saw himself as in the midst of one of many REFORMS that had happened before in the RCC. Yes, he wanted change - but not a new denomination... and the changes he desired were mostly focused on abuses that even Catholics today agree needed reform. BTW, much the same can be said of the English (Anglican) Reformation and of the Calvinist reformation.
2. Luther left the Catholic Church. Nope. The Catholic Church kicked him out. The Catholic Church excommunicated him. Now, I'll agree that by the time the RCC did this, things were bad ... and Luther pretty much mocked and laughed at the action. Sad. BUT history needs to get this right - Luther did not leave, he did not renounce his membership in the RCC (and to his death, considered himself Catholic), he was kicked out. A subtle point, perhaps, but one nearly all get wrong. Luther did not "split" the RCC... the RCC did that (just as it had done some 500 years earlier).
3. Luther had a new opinion about salvation. Nope. Luther's view was very orthodox Catholic. The bishop had made him a "Doctor of the Church" and that role meant he was responsible for spotting heresy and reporting that to him and the Church. It was his job. Well, indulgence sellers from Rome were all over Germany pushing the sale of these and doing so with the false claim that OUR actions is what determines salvation (and even impact that of others) - salvation by works. They were promoting a heresy known as "Pelagianism." A heresy that CATHOLICISM officially condemned. And with it they were promoting synergism, also a heresy. It was clear and bold... and this not only was heresy BUT also ripping off Germans to benefit the building of St. Peters and fattening the coffers of the profoundly rich RCC. Luther reported this - clearly expecting a "thank you for pointing this out" and the church correcting these sellers. Instead quite the opposite happened - much to the surprise of Luther. Luther's view of condemning Pelagianism and promoting that Jesus is the Savior (it's not synergistic) were solidly Catholic views, it's Catholicism that changed it's position at Trent shortly after Luther's death. Today, no supports the heresy of those indulgence sellers.... and some argue that Luther and the RCC largely misunderstood each other (and that may have some credence) but clearly Luther believed he was supporting traditional, orthodox, confessional Catholicism against the heresies of Pelagianism and synergism.
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