Christianity is the most populous religion on earth, with two billion believers worldwide — one-third of the Earth’s population. Yet it is also one of the most fiercely disputed religions, with hundreds, perhaps thousands of denominations and splinter sects, and many individual believers who do not associate themselves with any established church. Recent estimates place the Roman Catholic church at about a billion members worldwide (although not all are actively practicing), making it the largest single denomination. But the Mormon and Evangelical churches, who practice active proselytizing and missionary work throughout Russia, Africa, and Latin America, are also high in numbers.
And so Christianity is also the largest of the three monotheistic or “Abrahamic” religions, a term that includes Judaism and Islam, both of which also claim Abraham as their patriarch. Historically, Christianity bears a relationship to Judaism, its parent religion in the Western hemisphere, that resembles the way in which Buddhism developed from the Hindu culture of India. That is, it was born in a worldview dominated by Judaism, and shared many of its principles and much of its scripture. But Christianity also established itself almost immediately as a different tradition, and quickly grew apart.
Like the Buddha, Jesus of Nazareth was steeped in the culture and beliefs of his day — in his case, the Torah and the Hebrew prophets, whom he quoted extensively. But Jesus emphasized the compassion teachings of the Jews above ritual cleanliness and diet, seeking to restore the sense of communal love and support that had been damaged by the Roman occupation. Christians believe that Jesus was more than just a social reformer, however. The defining belief of Christianity is that Jesus is the only begotton Son of God, divinely engendered in his mother, Mary, through the action of the Holy Spirit. He is seen as God incarnate, the Word made flesh, in the language of the Gospel of John. But other facts about Jesus’ life and teachings are disputed by Christians, including many believing Christian biblical scholars, who insist that seeking the historical truth of the Gospel accounts of Jesus is not inconsistent with devout Christian faith.