The religions of Christianity and Islam are two very different religions with different beliefs and life styles, but are also alike in many ways. Each are the largest religions in the world, having over one billion followers in each. Islam's prophet was a man named Muhammad. Muhammad took many great interests in religion, and spent most of his time praying and meditating. When he was about 40, Muhammad's life changed after hearing the voice of the angel Gabriel. (Catherwood et. al 2003)