Christianity is an Abrahamic monotheistic religion based on the life and teachings of Jesus Christ as presented in the New Testament. Christianity is the world's largest religion, with over 2.4 billion adherents, known asChristians. Christians believe that Jesus is the Son of God and the savior of humanity whose coming as Christ or theMessiah was prophesied in the Old Testament.

Christian theology is expressed in ecumenical creeds. These professions of faith state that Jesus suffered, died, was buried, and was resurrected from the dead, in order to grant eternal life to those who believe in him and trust in him for theremission of their sins. The creeds further maintain that Jesus bodily ascended into heaven, where he reigns with God the Father, and that he will return to judge the living and dead and grant eternal life to his followers. His ministry, crucifixion and resurrection are often referred to as "the gospel", meaning "good news". The term gospel also refers to written accounts of Jesus's life and teaching, four of which—Matthew, Mark, Luke, and John—are considered canonical and included in Christian Bibles.

Christianity began as a Second Temple Judaic sect in the mid-1st century.Originating in Judea, it quickly spread toEurope, Syria, Mesopotamia, Asia Minor, Egypt, Ethiopia, and India and by the end of the 4th century had become the official state church of the Roman Empire. Following the Age of Discovery, Christianity spread to the Americas,Australasia, sub-Saharan Africa, and the rest of the world through missionary work and colonization. Christianity has played a prominent role in the shaping of Western civilization