Martin Luther (1483-1546) is one of the most important persons in history. He fearlessly opposed Roman Catholic teachings and practices that ran counter to what is found in the Bible and early Christianity. His rebellion against Rome was the greatest single event leading to the Reformation and the establishment of Protestantism. Ironically, the Reformation, with its emphasis on scripture and rejection of long-standing tradition, led to schisms within Protestantism itself. In many cases, this was because some Protestant leaders emphasized some things, while others emphasized different ideas. John Calvin, for example, emphasized the concept of predestination, an idea also advanced...