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He wrote up these issues in the "95 theses" -- http://www.google.com/search?q=martin+luther+95+theses&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a
Check some of these sites for the influence he had on later events:
http://www.google.com/search?q=martin+luther+influence&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a