Christianity originated from the life and teachings of Jesus Christ. The religion is based on beliefs outlined in the Christian Bible, which includes the Old Testament and New Testament. The New Testament documents Jesus' ministry and the establishment of the early Christian church. It was written in Greek between 45-140 AD and collected over centuries. Christianity teaches that God sent Jesus as the savior to achieve salvation for humanity. Key practices of Christian worship take place in churches and involve baptism, communion, and reflection on Jesus' life and teachings.