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Rastafarianism does not worship the same God as the God of the bible. They believe that Emperor Haile Selassie of Ethiopia, who claimed he was a descendant of King Solomon and Queen of Sheba was their messiah. At the time, Ethiopia was the only country in Africa never to have been ruled by a colonial power, so it was like a utopia to the descendants of slaves in the diaspora that there was a kingdom in Africa ruled by an African King.
Emperor Selassie's name before he ascended to the throne was Ras Tafari. He himself was an Orthodox Christian. When he heard that there was a cult in Jamaica that believed he was a messiah, he went to visit Jamaica where he was met on the tarmac by a stoned crowd of worshippers and this was reported to have astonished him. He then despatched one of the orthodox ministers to go and teach them real faith in Jesus Christ and not in him. Unfortunately he was assassinated not long after and no more efforts to establish a church there were made.