Christianity
Christianity is the world's largest religion, with approximately 2.4 billion adherents across every inhabited continent. Founded in the first century CE on the life, death and resurrection of Jesus of Nazareth, it grew from a small Jewish sect in Roman Palestine into the official religion of the Roman Empire in 380 CE and the dominant faith of medieval Europe; today its centre of gravity has shifted to the global South.
"The Anointed One" — the Greek translation of the Hebrew Mashiach ("Messiah"). Christians confess Jesus of Nazareth (c. 4 BCE – c. 30 CE) as the Messiah promised to Israel, the eternal Son of God incarnate, who died and rose again for the redemption of humanity.
Founder and history
Jesus was born in Bethlehem to Mary (Mariam, of Nazareth) and grew up at Nazareth in Galilee. After roughly three years of itinerant preaching, healing and gathering twelve apostles, he was crucified at Golgotha, Jerusalem, under the Roman governor Pontius Pilate, c. 30 CE. Christians believe he rose from the dead on the third day and ascended to heaven forty days later, sending the Holy Spirit on the apostles at Pentecost.
| Phase | Approx. dates | Key event |
|---|---|---|
| Apostolic | 30–100 CE | Mission of the Twelve; Paul's letters |
| Persecution & growth | 100–313 CE | Roman persecutions; martyrs |
| Imperial Christianity | 313–476 | Edict of Milan (313); Council of Nicaea (325); Theodosius makes Christianity state religion (380) |
| Patristic | 100–700 | Church Fathers; ecumenical councils |
| Great Schism | 1054 | East-West split (Catholic / Orthodox) |
| Crusades | 1095–1291 | Holy Land campaigns |
| Reformation | 1517– | Luther, Calvin; Protestantism |
| Modern | 1517–present | Counter-Reformation, missions, ecumenism |
Scriptures: the Bible
The Christian Bible comprises:
Old Testament
The 39 books of the Hebrew Tanakh (in Protestantism) or 46 books including the deuterocanonical writings (in Roman Catholicism and Orthodoxy). Christians read it as preparation for Christ.
New Testament
27 books in Koine Greek, composed c. 50–110 CE:
| Section | Books | Content |
|---|---|---|
| Four Gospels | Matthew, Mark, Luke, John | Life and teachings of Jesus |
| Acts of the Apostles | 1 book | Early church mission |
| Pauline epistles | 13 letters | Doctrinal and pastoral letters |
| General epistles | Hebrews, James, 1–2 Peter, 1–3 John, Jude | Pastoral teaching |
| Revelation | 1 book | Apocalyptic vision |
The earliest Gospel is Mark (c. 65–70 CE); the latest text is generally taken to be 2 Peter or the Pastoral Epistles.
- Founder: Jesus of Nazareth (c. 4 BCE – c. 30 CE).
- Scripture: Bible (Old Testament + New Testament).
- Core doctrines: Trinity, Incarnation, Atonement, Resurrection.
- Edict of Milan: 313 CE (Constantine).
- First Council of Nicaea: 325 CE; Nicene Creed.
- Great Schism: 1054 — Catholic/Orthodox split.
- Protestant Reformation: 1517 (Martin Luther's 95 Theses, Wittenberg).
- Vatican II Council: 1962–1965 — Catholic aggiornamento.
- Adherents: ~2.4 billion (largest world religion).
Core doctrines
The classical creed of Christianity is the Nicene Creed (325, expanded 381). Its central affirmations are:
- One God in three persons — Trinity: Father, Son, Holy Spirit.
- The Incarnation — the eternal Son became human as Jesus Christ.
- The Atonement — Christ's death reconciles humanity with God.
- The Resurrection — Christ rose bodily on the third day.
- The Second Coming and Last Judgment — Christ will return.
- The Church — one, holy, catholic and apostolic.
- Baptism for the forgiveness of sins.
- The resurrection of the body and life everlasting.
The Trinity doctrine — defined at Nicaea (325) and Constantinople (381) — distinguishes Christianity sharply from Jewish and Islamic strict monotheism.
Major branches
Roman Catholicism
The largest Christian body (~1.3 billion), headed by the Pope at Rome. Distinctive features:
- Seven sacraments: Baptism, Confirmation, Eucharist, Reconciliation, Anointing, Matrimony, Holy Orders.
- Papal authority and infallibility (defined 1870).
- Marian doctrines (Immaculate Conception, Assumption).
- Religious orders (Benedictines, Franciscans, Dominicans, Jesuits).
Eastern Orthodoxy
~220 million; centred on autocephalous patriarchates (Constantinople, Alexandria, Antioch, Jerusalem, Moscow, etc.). Distinctive features:
- Rejects papal supremacy and the filioque clause of the Western creed.
- Liturgical centrality (Divine Liturgy of St John Chrysostom).
- Veneration of icons; theology of theosis (deification).
Oriental Orthodoxy
~60 million (Coptic, Ethiopian, Armenian, Syriac); split from the mainstream after the Council of Chalcedon (451) over Christology.
Protestantism
~900 million across many families:
- Lutheran — from Martin Luther (1517).
- Reformed / Presbyterian — from John Calvin (1509–1564).
- Anglican — from the English Reformation (1534); Henry VIII, Book of Common Prayer.
- Baptist — believer's baptism by immersion.
- Methodist — from John Wesley (1703–1791).
- Pentecostal / Charismatic — from 1906 Azusa Street revival; now ~600 million worldwide.
The seven ecumenical councils
Recognised by Catholic and Orthodox traditions:
| Council | Date | Key issue |
|---|---|---|
| Nicaea I | 325 | Arianism; Nicene Creed |
| Constantinople I | 381 | Trinity; Holy Spirit |
| Ephesus | 431 | Mary as Theotokos |
| Chalcedon | 451 | Two natures of Christ |
| Constantinople II | 553 | Three Chapters |
| Constantinople III | 680–681 | Two wills of Christ |
| Nicaea II | 787 | Icons |
Festivals
| Festival | Occasion | Date |
|---|---|---|
| Christmas | Nativity of Christ | 25 December (W); 7 January (E) |
| Epiphany | Manifestation to Magi | 6 January |
| Lent | 40 days of fasting | Feb–Mar |
| Good Friday | Crucifixion | Friday before Easter |
| Easter | Resurrection | First Sunday after the spring full moon |
| Pentecost | Descent of the Holy Spirit | 50 days after Easter |
| All Saints | Saints of the Church | 1 November |
The Reformation and after
Martin Luther (1483–1546) posted his 95 Theses at Wittenberg on 31 October 1517, attacking the sale of indulgences. The Reformation produced the Protestant churches; the Catholic Council of Trent (1545–1563) responded with the Counter-Reformation. Wars of religion (1524–1648) culminated in the Peace of Westphalia (1648).
Modern Christianity
- Vatican II Council (1962–1965) — opened Catholic aggiornamento; Nostra Aetate (1965) on relations with non-Christian religions.
- World Council of Churches — founded 1948.
- Demographic shift — Christianity's majority population is now in Africa, Latin America and Asia.
- Pentecostal explosion — fastest-growing Christian movement since 1906.
Contemporary status
Christianity is the majority religion of Europe, the Americas, sub-Saharan Africa, the Philippines, and pockets of East and Southeast Asia. It is a minority religion in Muslim-majority states (~2.6% of Pakistan), India, China, Japan and the Arab world. The Pope (currently Pope Leo XIV, elected 2025, succeeding Pope Francis who served 2013–2025) leads the world's largest Christian body.
For CSS, fasten five facts: (1) Jesus of Nazareth (c. 4 BCE – c. 30 CE); (2) Edict of Milan 313 / Nicaea 325; (3) Great Schism 1054 (Catholic/Orthodox); (4) Reformation 1517 — Martin Luther's 95 Theses; (5) Vatican II Council 1962–1965 and Nostra Aetate 1965.
Conclusion
Christianity remains the world's largest religion, shaped by two millennia of councils, schisms and reformations. Its core confession — that Jesus of Nazareth is the Messiah and Son of God — distinguishes it equally from Judaism (which awaits the Messiah) and Islam (which honours Jesus as a prophet of the highest rank but rejects the Trinity). Its modern history is the story of demographic shift to the global South and increasing dialogue with other faith traditions.