Christianity is today the world’s most widespread religion, with more than a billion members, mainly divided between the Roman Catholic, Protestant, and Eastern Orthodox Churches. It originated among the Jewish followers of Jesus of Nazareth, who believed that he was the promised Messiah (or ‘Christ’), but the Christian Church soon became an independent organization, largely through the missionary efforts of St. Paul. In 313 Constantine ended official persecution in the Roman Empire and in 380 Theodosius I recognized it as the state religion. Most Christians believe in one God in three Persons (the Father, the Son, and the Holy Spirit) and that Jesus is the Son of God who rose from the dead after being crucified; a Christian hopes to attain eternal life after death through faith in Jesus Christ and tries to live by his teachings as recorded in the New Testament
Middle English: from Old French crestiente, from crestien 'Christian', influenced by late Latin christianitas, from Latin Christianus, from Christus 'Christ'