Christianity

Overview

Christianity is the religion centred on Jesus of Nazareth, a Jewish teacher executed by the Romans around 30 CE, whom Christians acknowledge as the Christ, the Son of God and the saviour of humanity. It grew out of Judaism and keeps its faith in one God, whom most Christians confess as a Trinity of Father, Son and Holy Spirit. Its scripture, the Bible, joins the Hebrew Bible, which Christians call the Old Testament, to the New Testament. With an estimated 2.3 billion followers in 2020, it is the world's largest religion. Its churches fall broadly into Catholic, Protestant and Orthodox families, alongside fast-growing Pentecostal and independent movements. Born in the Middle East, it now has more followers in sub-Saharan Africa than anywhere else.^{[3–4, 7, 9–11]}

History

Jesus and the first believers c. 30–100 CE

Jesus, a Jewish preacher from Galilee, proclaimed the coming kingdom of God, gathered disciples and was crucified in Jerusalem on the orders of the Roman governor Pontius Pilate, probably around 30 CE. His followers soon reported that he had risen and appeared to them. At first they were a group within Judaism, led in Jerusalem by Peter and James. Paul of Tarsus, once a persecutor of the movement, took its message to non-Jews, and the decision to admit Gentiles without making them become Jews set the faith on course to be a separate religion.^[12–15]

Persecution, empire and creeds 64–451

For more than two centuries Christians were a minority, meeting in homes under bishops and facing bouts of Roman persecution, beginning when Nero blamed them for the fire of Rome in 64. Constantine, the first emperor to profess the faith, agreed with Licinius in 313 that all might worship freely, and in 325 called the Council of Nicaea, which declared the Son of one substance with the Father. Theodosius I made Nicene faith the imperial standard from 380. Disputes over Christ's nature then divided the churches: the Church of the East in Persia declared its independence in 424, and the churches of Egypt, Syria and Armenia rejected the Council of Chalcedon in 451.^[16–19]

Medieval East and West c. 600–1500

Missionaries carried the faith to the Slavs, and monks of the Church of the East reached Tang China in the 7th century. From the 630s Arab armies brought Syria, Egypt and Persia under Muslim rule; Christians there kept their churches and stayed numerous for centuries, but slowly became minorities. The Greek East and Latin West drifted apart over language, papal authority and doctrine. Mutual excommunications in 1054 came to symbolise the split, which hardened when crusaders sacked Constantinople in 1204, during the wars Latin Christians waged for the Holy Land from 1095 to 1291.^[20–23]

Reformation and worldwide expansion 1500–1800

In 1517 the German friar Martin Luther attacked the sale of indulgences, and the dispute grew into a contest over whether the pope or the Bible held final authority. The Reformation split Western Christianity into the Catholic Church and Protestant traditions, among them Lutheran, Reformed, Anglican and Anabaptist; Catholics answered at the Council of Trent (1545–63), and religious rivalries fed the Thirty Years' War (1618–48). Spanish and Portuguese expansion carried Catholicism to the Americas, Africa and Asia. In the Americas, conquest and forced labour devastated Indigenous peoples; a few missionaries, notably Bartolomé de Las Casas, denounced the abuses.^[24–27]

A global faith 1800–today

In the 19th century Protestant and Catholic missions spread across Africa, Asia and the Pacific, often alongside European empires, though much of the growth came through local catechists and Bible translations. Pentecostalism, which grew from a revival on Azusa Street, Los Angeles, beginning in 1906, spread worldwide. The World Council of Churches was founded in 1948, and the Catholic Second Vatican Council (1962–65) brought Mass in local languages. By 2020 sub-Saharan Africa held the largest share of the world's Christians, while numbers in Europe were falling and many raised as Christians had left the faith.^{[11, 28–31]}

Key moments

1. c. 30 CELife of Jesus · Galilee and Judea
2. c. 50 CEPaul's letters · Eastern Mediterranean
3. c. 80 CEThe Gospels are written · Eastern Mediterranean
4. c. 270 CEAntony and the desert monks · Egypt, east of the Nile
5. c. 301 CEArmenia becomes Christian · Vagharshapat, Armenia
6. 313 CEThe Edict of Milan · Milan and Nicomedia (İzmit)
7. 325 CECouncil of Nicaea · Nicaea (İznik, Türkiye)
8. c. 340 CEAksum turns to Christ · Aksum, Ethiopia
9. 367 CEAthanasius lists 27 books · Alexandria
10. 380 CETheodosius makes Nicene faith the law · Thessalonica
11. 431 CECouncil of Ephesus · Ephesus (Selçuk, Türkiye)
12. 451 CECouncil of Chalcedon · Chalcedon (Istanbul)
13. c. 530 CEBenedict writes his Rule · Monte Cassino, Italy
14. c. 537 CEThe temple of Isis at Philae is closed · Philae, near Aswan, Egypt
15. 537 CEHagia Sophia · Constantinople (Istanbul)
16. c. 726 CEByzantium bans its icons · Constantinople
17. 800 CECharlemagne crowned emperor · St Peter's Basilica, Rome
18. c. 863 CECyril and Methodius among the Slavs · Great Moravia (Czechia and Slovakia)
19. c. 957 CEOlga of Kyiv is baptised · Kyiv and Constantinople
20. 988 CEThe Baptism of Rus' · Kyiv
21. c. 1590 CEThe European witch trials · Europe, above all the German lands
22. 1670 CESpinoza's Treatise · Amsterdam
23. 1851 CEThe Taiping Heavenly Kingdom · Nanjing, China
24. 1859 CEDarwin's Origin of Species · London and Oxford, England
25. 1945 CEPancasila: Indonesia's five principles · Jakarta, Indonesia

Beliefs

Trinity

Christians believe in one God who exists as three persons, Father, Son and Holy Spirit, equal and sharing one divine being. The word does not appear in the New Testament; the doctrine was worked out in the 4th century, notably at the councils of Nicaea (325) and Constantinople (381), and nearly all churches affirm it.^[32]

Incarnation

God taking on human flesh

Christians hold that in Jesus the eternal Son of God became a human being. The Council of Chalcedon (451) defined him as one person in two natures, fully divine and fully human. Catholic, Orthodox and most Protestant churches accept this formula; the Oriental Orthodox churches confess the same Christ but word his unity differently.^[33–34]

Salvation

Christians hold that sin estranges humanity from God and that Jesus' crucifixion and his rising on the third day reconcile people to God. Paul wrote that without the resurrection faith would be empty, and it grounds the hope that the dead will rise to eternal life. Churches explain this atonement in several ways; Orthodox theology speaks of theosis, a sharing in God's life.^[35–36]

Holy Spirit and the Church

Christians believe the Holy Spirit came upon the first disciples at Pentecost and still guides believers, and the New Testament calls the community of believers the body of Christ. Catholics and Orthodox read scripture within the church's tradition and honour bishops as successors of the apostles; Protestants make the Bible the final authority.^[37–38]

Second Coming

Christians expect Christ to come again in glory as judge of all, living and dead, and to complete God's kingdom, with a new heaven and a new earth. Teachings on heaven, hell and, for Catholics, purgatory fill out this hope, and the Book of Revelation, which pictures the end, is read by some literally and by others symbolically.^[39]

Practice

Baptism

Baptism with water, almost always in the name of the Father, Son and Holy Spirit, is the rite of entry into the church. Catholic, Orthodox, Anglican and many Protestant churches baptise infants, while Baptists, Pentecostals and others baptise only those old enough to profess faith. Water may be poured or sprinkled, or the person fully immersed.^[40]

Eucharist and Sunday worship · εὐχαριστία

The Eucharist, also called Holy Communion, the Lord's Supper or the Mass, recalls Jesus' last meal with blessed bread and wine and is the central act of worship for most churches. Catholics and Orthodox believe Christ is truly present in it; some Protestants see a memorial. Most Christians worship on Sunday, the day of the resurrection, and say the Lord's Prayer, which Jesus taught according to the Gospels.^[41–43]

Sacraments and rites of passage

Catholic and Orthodox churches count seven sacraments, which mark the stages of life and faith: baptism, confirmation (chrismation), the Eucharist, penance, anointing of the sick, marriage and ordination. Most Protestant churches keep only baptism and the Lord's Supper as rites instituted by Christ, and some, such as Baptists, call them ordinances rather than sacraments.^[44]

Love of God and neighbour

In the Gospels Jesus sums up the law in two commandments: to love God with all one's being and one's neighbour as oneself. Christian ethics builds on these, and churches have long made care for the sick and poor a duty; healing played a part in the early church's growth, and Christian missionaries went on to found many hospitals, notably across Africa.^[45]

Holy days

Easter · Pascha

First Sunday after the first full moon of spring (22 March–25 April in the West)

The principal Christian festival, celebrating Jesus' resurrection. It closes Holy Week, which recalls his entry into Jerusalem, last supper and crucifixion. Orthodox churches reckon the date by the Julian calendar, so their Easter usually falls later.^[46]

Christmas

25 December; 7 January in churches using the Julian calendar

The feast of Jesus' birth, kept in Rome on 25 December from about 336 and prepared for by Advent. Orthodox churches that follow the Julian calendar keep it on what is 7 January in the Gregorian calendar; the Armenian Church keeps 6 January.^[47]

Lent

About forty days before Easter (February–April)

A season of fasting, prayer and almsgiving before Easter, recalling Jesus' forty days in the wilderness. Western churches begin it on Ash Wednesday; Eastern churches keep a Great Lent beginning on a Monday seven weeks before Easter.^[48]

People

Jesus of Nazareth

founder · c. 6–4 BCE – c. 30 CE

A Galilean Jew, baptised by John the Baptist, who had a short public career as a travelling preacher and healer before his crucifixion in Jerusalem. Christians call him Christ, Greek for 'anointed', translating the Hebrew 'Messiah', and most believe him to be God made human.^{[2, 49]}

Mary

saint · early 1st century CE

The mother of Jesus. The Gospels of Matthew and Luke say she conceived him as a virgin, and the Council of Ephesus upheld her title Theotokos, 'God-bearer'. Catholics and Orthodox honour her above all other saints; most Protestants respect her but reject prayer to her.^[50]

Peter

saint · died c. 64 CE

A Jewish fisherman whom Jesus named Cephas, 'Rock', and who led the twelve apostles. Early tradition says he died a martyr in Rome under Nero, and the Catholic Church regards him as the first pope.^[51]

Paul of Tarsus

saint · died c. 62–64 CE

A Jew from Tarsus who persecuted the early believers, then, after what he described as a vision of the risen Jesus, became the leading missionary to the Gentiles. Thirteen New Testament letters bear his name; scholars accept seven as certainly his.^[52–53]

Augustine of Hippo

scholar · 354–430

Bishop of Hippo in North Africa from 396 and perhaps the most influential Christian thinker after Paul. His Confessions, The City of God and his teaching on grace and predestination shaped Western theology, Catholic and later Protestant.^[54]

Scripture

The Bible

The Old Testament is the Hebrew Bible, counted by Protestants as 39 books; Catholic and Orthodox Bibles include further books, giving Catholics 46. The New Testament's 27 books are shared by all major churches, though agreement on the list took centuries.^[55]

The four Gospels

c. 70–110 CE

Matthew, Mark, Luke and John tell of Jesus' life, teaching, death and resurrection. The first three, the Synoptic Gospels, share so much material and wording that they can be read side by side; John follows its own order and has long theological discourses.^[56]

The Nicene Creed

325, enlarged 381

A statement of faith in the Trinity and in Christ, linked to the councils of Nicaea (325) and Constantinople (381). It is the one creed accepted by Catholic, Orthodox, Anglican and major Protestant churches, though East and West still differ over the Western addition that the Spirit proceeds from the Father 'and the Son'.^[57]

Places

Church of the Holy Sepulchre, Jerusalem

PSE · UNESCO World Heritage, 1981

Built over the traditional site of Jesus' crucifixion and tomb, Constantine's first church here was dedicated around 336; the present building dates mainly from Crusader rebuilding and 1810. Greek, Latin, Armenian, Coptic and other churches share it.^[58]

Church of the Nativity, Bethlehem

PSE · UNESCO World Heritage, 2012

Christian tradition has placed Jesus' birth in a cave here since the 2nd century. The first church was completed in 339, and the building that replaced it after a 6th-century fire still stands.^[59]

Hagia Sophia, Istanbul

TUR · UNESCO World Heritage, 1985

Justinian I built this great domed church in 532–537 as the cathedral of Constantinople. After the Ottoman conquest of 1453 it became a mosque, then a museum in 1935, and a mosque again in 2020.^[60]

Rock-hewn churches of Lalibela

ETH · UNESCO World Heritage, 1978

Eleven churches carved from solid rock in the Ethiopian highlands, credited by tradition to King Lalibela (late 12th–early 13th century), who meant them as a new Jerusalem. They remain a pilgrimage centre of the Ethiopian Orthodox Tewahedo Church.^[61]

Where it spread

Art & objects

Public-domain objects from museum collections. Select one to see it at the museum.

The AnnunciationMantua, 1484/1519The Annunciation, from The Life of the VirginGermany, c. 1503, published 1511The NativityAustria, 1507–10The NativityItaly, c. 1465The Baptism of ChristItaly, 1500–05The CrucifixionItaly, 1401–04Stonyhurst Hours (Use of Sarum)Flanders, c. 1400–10Resurrection of ChristHolland, c. 1665CrucifixionGermany, 1508Virgin and ChildFrance, c. 1245Christ EnthronedGermany, n.d.CrucifixMeuse, c. 1150Plaque with the CrucifixionLimoges, 1200–10Saint Gregory as AuthorGermany, 1188/1200

Numbers

Christians worldwide

c. 2.3 billion (2020)^[9]

Pew: 2.3 billion, 28.8% of humanity, in 2020. The World Christian Database, counting more broadly, gives 2.5 billion for 2020 and 2.6 billion for 2025.

Catholics

About half of all Christians^[62]

Pew: 50% of Christians in 2010. World Christian Database: 1.27 billion Catholics in 2025.

National censuses

Source: Australian Bureau of Statistics, Census of Population and Housing 2021, 'Religious affiliation in Australia' (Table 4), CC BY 4.0. Source: Office of the Registrar General & Census Commissioner, India, Census of India 2011, Table C-01 Population by religious community and its appendix, under the Government Open Data License – India. Source: Office for National Statistics licensed under the Open Government Licence v.3.0 Adapted from Statistics Canada, Table 98-10-0342-01 Religion by visible minority and generation status: Canada, provinces and territories, census metropolitan areas and census agglomerations with parts, released 2022-10-26. This does not constitute an endorsement by Statistics Canada of this product. Source: Stats NZ, 2018 Census, licensed by Stats NZ for re-use under the Creative Commons Attribution 4.0 International licence.

How we know

The historical Jesus

Historians almost all agree that Jesus existed. Besides the New Testament, the Jewish historian Josephus and the Roman historian Tacitus mention him, though they confirm little beyond his existence and execution under Pilate. Scholars broadly agree that he was a Jewish preacher from Galilee, baptised by John, who announced the kingdom of God and was crucified by the Romans. Whether he rose from the dead or was divine is a matter of faith that historical method cannot test.^[63–65]

How the Gospels were written

The Gospels were written in Greek, decades after Jesus' death, and circulated anonymously; the names Matthew, Mark, Luke and John come from later tradition. Most scholars date Mark to around 70 CE, Matthew and Luke to roughly the 80s, and John to about 90–110. The prevailing view is that Matthew and Luke both drew on Mark and on a lost collection of sayings called Q. Paul's letters, from around 50 onward, are older than all four.^[66–69]

Common misconceptions

Glossary

Gospel · εὐαγγέλιον

Greek euangelion, 'good news', rendered in Old English as god-spell: the Christian message about Jesus, and each of the four books that tell his story.^[71]

Christ · Χριστός

A title, not a surname: Greek christos, 'anointed', translating the Hebrew for Messiah.^[72]

Apostle · ἀπόστολος

Greek for 'one who is sent': the twelve disciples Jesus chose, and others such as Paul.^[73]

Sacrament

A rite that churches believe conveys God's grace through visible signs; Augustine called it the visible form of an invisible grace. Catholics and Orthodox count seven, most Protestants two.^[74]

Saint

A holy person honoured after death. The first saints were martyrs; Catholics and Orthodox ask saints to pray for them, and the Catholic Church names saints by canonisation.^[75]

Icon · εἰκών

A sacred image of Christ, Mary or a saint, central to Orthodox devotion; the Second Council of Nicaea (787) upheld its veneration against the Iconoclasts.^[76]

Ecumenism

From Greek oikoumenē, 'the inhabited world': the movement for unity among churches, which took shape after the Edinburgh missionary conference of 1910.^[77]

Theotokos · Θεοτόκος

Greek for 'God-bearer': Mary's title as mother of the incarnate Son, upheld at the Council of Ephesus in 431.^[78]