Christianity is a monotheistic religion centered on the life, teachings, death, and resurrection of Jesus Christ. It emerged within Judaism in the first century CE in the eastern Roman Empire. Christians identify Jesus as the Messiah, or Christ, and understand his significance through scripture, worship, and the life of the church. Christianity encompasses numerous communities rather than a single worldwide institution, with substantial differences in doctrine and organization alongside shared historical origins. (pluralism.org)
Origins and early development
Jesus was a Jewish teacher whose ministry took place in Galilee and Judaea. He taught about the kingdom of God, repentance, and love of God and neighbor. Roman authorities executed him by crucifixion in Jerusalem around 30 CE. His followers proclaimed that he had risen from the dead; the resurrection became foundational to Christian faith and its understanding of Jesus’ identity. Historical accounts distinguish the execution of Jesus from the resurrection as a religious claim recorded in Christian sources. (centernet.pcusa.org)
The earliest communities were Jewish, but the movement increasingly included non-Jews. Paul the Apostle established and supported congregations around the Mediterranean. His surviving letters, largely written during the 50s CE, are among the earliest Christian writings. The four canonical Gospels emerged later in the first century, preserving distinct accounts of Jesus’ ministry and significance. Christianity gradually developed institutions and an identity distinguishable from other Jewish traditions. (pluralism.org)
Christians experienced periods of persecution under Roman rule. In 313, an agreement associated with Constantine and Licinius granted religious toleration, including protection for Christian worship. Constantine convened the Council of Nicaea in 325 to address doctrinal disagreements, particularly concerning Christ’s divinity. Imperial support subsequently transformed the church’s public position. (pluralism.org)
Beliefs and theology
Most major Christian traditions affirm the Trinity: one God in three persons, Father, Son, and Holy Spirit. They understand Jesus as both divine and human, expressing the doctrine of the Incarnation. These formulations distinguish persons without treating them as three separate gods. Some communities identifying as Christian do not accept the traditional Trinitarian formulation. (centernet.pcusa.org)
Salvation concerns deliverance from sin and death and reconciliation with God through Christ. Christian traditions emphasize divine grace, but differ over the relationship between faith, works, sacraments, and human freedom. Beliefs about judgment, eternal life, and Christ’s return also receive different interpretations. Christian ethics commonly draws on Jesus’ teachings concerning love, forgiveness, and care for others. (centernet.pcusa.org)
Scripture and authority
The Bible contains the Old Testament and the New Testament. The Old Testament incorporates scriptures inherited from Judaism, although its contents and arrangement differ among Christian traditions. The New Testament comprises 27 books: four Gospels, Acts of the Apostles, letters to communities and individuals, and Revelation. Its collection and recognition developed over several centuries rather than through a single decision. (centernet.pcusa.org)
Christians differ in how they relate scripture to church tradition and teaching authority. Catholic and Orthodox traditions give substantial authority to inherited ecclesiastical teaching; many Protestants emphasize scripture as the final standard of doctrine. Biblical interpretation ranges from literal readings to approaches attentive to literary genre, symbolism, and historical context. These differences affect both theological teaching and everyday religious practice. (pewresearch.org)
Major traditions
Catholicism recognizes the authority of the bishop of Rome, the pope, and includes both Latin and Eastern Catholic churches. Eastern Orthodoxy consists of self-governing churches sharing a sacramental and doctrinal tradition without accepting universal papal jurisdiction. Their separation developed over centuries; the exchanges of excommunication in 1054 conventionally mark the East–West Schism. (pewresearch.org)
Oriental Orthodox churches, including the Coptic, Armenian, and Ethiopian traditions, have a distinct history associated with disagreements over the Council of Chalcedon in 451. The Church of the East represents another historically distinct eastern tradition. Neither should be treated simply as a subdivision of Eastern Orthodoxy. (pewresearch.org)
Protestantism developed from the sixteenth-century Reformation. It includes Lutheran, Reformed, Anglican, Baptist, Methodist, and numerous other traditions. Their structures range from episcopal leadership to representative assemblies and autonomous congregations. Pentecostalism, emerging prominently in the early twentieth century, emphasizes experiences understood as gifts of the Holy Spirit. (pluralism.org)
Worship and religious life
Christian worship commonly includes prayer, scripture readings, preaching, and singing. Most churches gather principally on Sunday. Two widely shared rituals are baptism, associated with entry into Christian life, and the Eucharist, also called Holy Communion or the Lord’s Supper. Churches differ over infant baptism, Christ’s presence in communion, and who may participate. (centernet.pcusa.org)
Christmas celebrates Jesus’ birth, while Easter celebrates his resurrection. Other observances include Lent, Good Friday, Ascension, and Pentecost. Practices vary across traditions and calendars. Christian religious life also includes charitable service and, in some traditions, monasticism, whose organized forms developed prominently during late antiquity. (centernet.pcusa.org)
Global distribution and cooperation
A Pew Research Center study published in June 2025 estimated approximately 2.3 billion Christians in 2020, representing 28.8% of the world’s population. These are estimates for 2020, not the publication year. Sub-Saharan Africa contained 31% of Christians worldwide, compared with 22% in Europe, reflecting Christianity’s geographically diverse distribution. (pewresearch.org)
Ecumenism seeks greater cooperation and unity among Christian churches. The World Council of Churches’ 1982 document Baptism, Eucharist and Ministry identified areas of theological convergence alongside continuing differences. Mutual recognition of baptism and ministry, and participation in communion across church boundaries, remain important subjects of dialogue. (oikoumene.org)