Martin Luther lived at a time when the Roman Catholic Church was extremely corrupt. Doesn't that look a bit like the way the Church is today? Anyway Luther thought there should be something better than Roman Catholicism and started Protestantism.
| “ | "as soon as the coin in the coffer rings, the soul from purgatory springs." | ” |
Luther thought the Church was too wealthy and made itself even wealthier by selling indulgences. The Church persuaded people if they gave money to the already wealthy Church their personal sins or the sins of other people they wanted to help would be forgiven. The Church didn't like all this criticism and decided Luther was a Heretic. [2]
Roman Catholicism taught and teaches that the Pope and other organs of the Church hierarchy are authoritative in interpreting the Bible and establishing matters of Faith and doctrine. Naturally different Protestants interpreted the Bible differently and by the end of his life Luther disagreed strongly with some other influential Protestants. Disagreement between different Sects and denominations of Protestants have continued ever since.
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There is a good and a a bad side to Christianity, see the category page