Christianity

In the 1st century CE, in Roman-ruled Judea, among the followers of Jesus of Nazareth after his crucifixion (c. 30–33 CE).

The disciples' proclamation that Jesus had risen; Paul's missionary journeys across the Roman world; the destruction of the Jerusalem Temple (70 CE), which hastened the separation from Judaism; waves of Roman persecution; then Constantine's conversion and the Edict of Milan (313 CE) legalizing the faith.

The apostles (Peter, John, James); Paul of Tarsus, whose letters are the earliest Christian writings; the Gospel writers; and the church fathers (Irenaeus, Athanasius, Augustine). The ecumenical councils, beginning at Nicaea (325 CE), fixed the creeds.

Along Roman roads and in the Greek language across the empire; made the Roman state religion in 380 CE; carried through Europe by missions; split East and West (1054); then carried worldwide by European colonial expansion and missionary movements — its fastest growth today is in Africa and the Global South.

About 2.4 billion people — roughly 31% of humanity, the largest worldview by adherents. Largest populations: the United States, Brazil, Mexico, Russia, the Philippines, and Nigeria.

Nicaea and the creeds (4th century); the Great Schism between Catholic and Orthodox (1054); the Protestant Reformation (1517); the modern encounter with historical criticism and European secularization; and the 20th-century Pentecostal explosion that moved Christianity's center of gravity southward.

Sin: humanity has turned away from God, and this broken relationship distorts everything else. The New Testament states that 'all have sinned and fall short of the glory of God' (Romans 3:23).

From the Fall: Genesis tells how humanity's first disobedience let sin and death into the world (Romans 5:12). Augustine taught that evil is not a thing God made but a corruption of good, born of the misuse of free will.

The human heart. Jesus taught that evil comes from within — 'out of the heart come evil thoughts' (Mark 7:21) — so the deepest break is spiritual: a will turned away from God, which outward law-keeping alone cannot mend.

God's own rescue: the New Testament teaches that God became human in Jesus Christ, died for humanity's sins, and rose from the dead — offering forgiveness and new life as a free gift of grace, received by faith (John 3:16; Ephesians 2:8–9).

Repentance and faith in Christ, marked by baptism, then a lifelong transformation through the Holy Spirit within the church. The branches describe the road differently: Catholics and Orthodox stress the sacraments as channels of grace; Protestants stress faith alone.

Fully — but not by human effort, and not in this life. Christian teaching holds that sin was decisively defeated at the cross, is progressively overcome in the believer, and will be abolished only when Christ returns and God makes 'all things new' (Revelation 21:5).

The person is 'born again' into a life of love (John 3:3; Galatians 5:22); society is leavened by communities that practice forgiveness, charity, and care for the weak; and the world itself, Paul writes, waits to be set free — a renewed creation, not an escape from it (Romans 8:21).

God, revealed above all in Jesus Christ — 'I am the way, the truth, and the life' (John 14:6) — and witnessed to in the Bible. Protestants make Scripture the final authority; Catholics and Orthodox place Scripture within the church's living Tradition.

Revelation first — God's self-disclosure in Christ and Scripture — with reason, tradition, and experience in its service. Aquinas argued that reason alone can reach some truths about God, while others, like the Trinity and the Incarnation, come only by revelation.

Because, Christians argue, God confirmed it inside history: the resurrection of Jesus vindicated his claims, and the apostles testified as eyewitnesses at the cost of their lives (1 Corinthians 15:3–8; Acts 2:32). Later thinkers add the faith's inner coherence and its power to transform lives.

By testing every claim against Scripture and the apostolic teaching fixed in the creeds — 'test everything; hold fast what is good' (1 Thessalonians 5:21) — and by fruits: Jesus said false teachers are known by what their lives produce (Matthew 7:15–20). Catholics and Orthodox add the church's teaching office as the final safeguard.

Real and fixed: right and wrong are grounded in God's own character and law, not in any human vote. Paul writes that the law's demands are 'written on the hearts' even of those without Scripture (Romans 2:14–15) — the seed of the natural-law tradition developed by Aquinas and defended in plain terms by C.S. Lewis.

Yes, but partly and by God's help: creation itself displays his power (Romans 1:20), and revelation displays his character — yet Paul concedes that 'now we see in a mirror, dimly' (1 Corinthians 13:12). Full knowledge belongs to the world to come.

The core is fixed — 'the faith once for all delivered to the saints' (Jude 3), summarized in the creeds — while understanding grows: Newman argued that true doctrine develops like a living idea, and Protestants speak of a church 'always being reformed' by Scripture.

The Bible: the Old Testament (the Hebrew Scriptures) and the New Testament — 27 books written in Greek: four Gospels, the Acts, twenty-one letters, and Revelation. Catholic and Orthodox Bibles include extra Old Testament books (the deuterocanon) that Protestant Bibles omit.

Jesus himself wrote nothing; his words were carried orally, then written: Paul's letters first (c. 50–60 CE), the Gospels between roughly 65 and 100 CE. The books circulated separately, were copied by hand across the Roman world, and were gradually recognized as one canon — the Easter letter of Athanasius (367 CE) gives the first exact list of the 27 New Testament books.

Christians claim the writers were inspired by God (2 Timothy 3:16); no promise of miraculously protected copies is made. The record: about 5,800 Greek manuscripts, with fragments from the 2nd century — richer attestation than any other ancient text — but they contain hundreds of thousands of copying variants, the vast majority trivial (spelling, word order). Most textual scholars judge the original text recoverable with high confidence; skeptics led by Bart Ehrman stress that the originals are lost and that a few variants touch doctrine.

One long story of covenant and rescue: creation, fall, Israel, Christ, church, new creation — with the kingdom of God at the center of Jesus' preaching. The style spans genres: law, history, poetry (the Psalms), prophecy, Gospel biography, letters, and apocalyptic vision.

Love God with all your heart, and your neighbor as yourself (Matthew 22:37–40); Christ died for sins and was raised (1 Corinthians 15:3–4); salvation is God's gift of grace (Ephesians 2:8); forgive as you have been forgiven (Matthew 6:14); and treat others as you would be treated (Matthew 7:12).

By genre, in the main: history read as history, parables as stories with a point, Revelation's visions as symbol. The historic churches read Scripture in context and through the church's teaching; some conservative Protestants read it strictly literally, while liberal Christians take much of it symbolically.

The church fathers (Origen, Chrysostom, Augustine); the medieval schools culminating in Aquinas; the Reformation commentaries of Luther and Calvin; and, since the 18th century, modern historical criticism — which the churches have variously resisted, absorbed, or embraced.

Yes, and Christian scholars document them openly: the longer ending of Mark (16:9–20) and the story of the woman caught in adultery (John 7:53–8:11) are absent from the earliest manuscripts and are bracketed in modern Bibles, and the Trinitarian wording of 1 John 5:7 is a late addition. Scholars also debate how the first three Gospels relate — most hold that Matthew and Luke drew on Mark — and the branches differ over the Old Testament deuterocanon.

They claim divine inspiration — 'all Scripture is God-breathed' (2 Timothy 3:16) — yet also human care: Luke opens by describing his investigation among eyewitnesses (Luke 1:1–4). John states the purpose plainly, 'these are written that you may believe' (John 20:31), and the message is addressed to 'all nations' (Matthew 28:19).

Yes: one God, creator of everything, personal, holy, and loving — and, uniquely among the monotheisms, a Trinity: Father, Son, and Holy Spirit, one being in three persons (Matthew 28:19). Christians hold that God's character is seen most clearly in Jesus: 'whoever has seen me has seen the Father' (John 14:9).

Both: the creed confesses God as maker 'of all things visible and invisible.' The physical world is created good — Christian hope is bodily resurrection, not escape from matter — and there is also a spiritual order: souls, angels, and God himself.

Yes. Christian tradition teaches that each person has a soul that outlives bodily death and is reunited with a resurrected body at the end (Matthew 10:28; 1 Corinthians 15). Theologians differ on the details — Aquinas saw the soul not as a ghost inside the body but as its 'form,' what makes it a living human.

Scripture offers no definition; Christian thinkers treat consciousness as the life of the rational soul, part of being made in God's image. Most hold it cannot be fully reduced to brain chemistry, though Christian philosophers today debate dualism against more body-centered views.

The one soul God created and knows by name: identity rests not on memory or the body's matter — both of which change — but on being the same creature continuously held in existence and known by God (Psalm 139). This grounds the Christian claim that the very person who dies is the one who is raised.

Both dignified and damaged: made in God's image (Genesis 1:27), yet born with a nature inclined toward sin — the doctrine of original sin, classically stated by Augustine. Orthodox Christians soften the formula: from Adam we inherit death and weakness, not personal guilt.

Yes — humans choose and answer for their choices — but the will is weakened by sin and needs God's grace. How grace and freedom fit together is Christianity's oldest internal debate: Augustine against Pelagius, and later Calvinists (predestination) against Arminians (free response).

A single creature with two sides made for each other: the body is not the soul's prison but its partner — 'a temple of the Holy Spirit' (1 Corinthians 6:19). That is why the Christian hope is the resurrection of the body, not a bodiless heaven.

Because God, who lacks nothing, freely chose to create out of love (Revelation 4:11). Christian philosophy presses the point as the argument from contingency: everything in the universe might not have existed, so the final explanation must be a being that cannot not exist — God, as Aquinas argued.

God created it from nothing: 'In the beginning God created the heavens and the earth' (Genesis 1:1). Most traditions accept the Big Bang and the universe's age as the science of how — a Catholic priest, Georges Lemaître, first proposed the Big Bang — while a minority reads Genesis as a literal six days.

God's own character, expressed in his commands and summed up by Jesus in two: love God completely, and love your neighbor as yourself — 'on these two commandments hang all the Law and the Prophets' (Matthew 22:40). Love, Paul adds, is the fulfillment of the law (Romans 13:10).

Faith, hope, and love — 'the greatest of these is love' (1 Corinthians 13:13) — with the Beatitudes' humility, mercy, purity of heart, and peacemaking, and the Spirit's fruit: joy, peace, patience, kindness, gentleness, self-control (Galatians 5:22–23). Its most distinctive demand is forgiveness — even of enemies.

The Ten Commandments' list — idolatry, murder, adultery, theft, false witness, coveting — which Jesus pushed to the heart: hatred counts as murder, lust as adultery (Matthew 5:21–28). The letters add greed, drunkenness, and sexual immorality; in the tradition's ranking, the deadliest sin is pride.

Daily prayer — Jesus gave the Lord's Prayer as the model (Matthew 6:9–13) — Scripture reading, Sunday worship, and the Lord's Supper, celebrated weekly in Catholic and Orthodox practice; plus fasting seasons such as Lent, confession, and giving to the poor.

Relationships run on love and forgiveness — 'seventy times seven' (Matthew 18:22); work is done 'as for the Lord, not for men' (Colossians 3:23); hardship is endured with hope, since suffering 'produces perseverance, character, and hope' (Romans 5:3–4); and no one carries life alone — believers are one body, bearing one another's burdens (Galatians 6:2).

Jesus Christ himself — the stated goal is 'to be conformed to the image of his Son' (Romans 8:29): a person who loves God and enemies alike, serves rather than dominates, speaks truth, and lays down life for others. The saints are honored as partial portraits of that pattern.

Forgiveness upon repentance: 'if we confess our sins, he is faithful and just to forgive us' (1 John 1:9). Catholics and Orthodox practice confession as a sacrament; all traditions expect repair of harm and allow church discipline for the unrepentant (Matthew 18:15–17) — yet the door back is never closed, as the parable of the prodigal son insists (Luke 15).

To know, love, and glorify God, and to love others: the Westminster Catechism answers that man's chief end is 'to glorify God and enjoy him forever.' Augustine made it personal: 'you have made us for yourself, and our heart is restless until it rests in you.'

The soul goes to God's presence or away from it; then, at Christ's return, the dead are raised bodily and judged (John 5:28–29). Catholics add purgatory — a final purification for the saved — which Orthodox and Protestants do not teach.

Salvation: forgiveness of sins now, God's presence through every circumstance, and bodily resurrection into eternal life — 'I am the resurrection and the life' (John 11:25). It is offered as a gift, not a wage (Romans 6:23).

For creation: a renewed heavens and earth where God dwells with humanity and 'death shall be no more' (Revelation 21:4). For each person: eternal life with God, or final separation from him — hell, which the mainstream holds to be real while Christians debate its nature: unending punishment, destruction, or (a minority hope) finally empty.

A final judgment: history runs in a straight line to Christ's return, when — in the creed's words — 'he will come again to judge the living and the dead.' There are no cosmic cycles and no dissolving of the self: each person is raised and answers for their own life (2 Corinthians 5:10).

As a family and a story: weekly worship with singing and communion, the felt experience of forgiveness and God's nearness in prayer, and belonging to a congregation that marries, buries, feeds, and consoles its members. For many the hinge is conversion — a personally dated before-and-after.

Three great branches: Catholic (about half of all Christians, under the pope), Protestant (about 37%, itself many families — Lutheran, Reformed, Anglican, Baptist, Methodist, Pentecostal), and Orthodox (about 12%, Eastern and Oriental). Pentecostalism, born in the early 20th century, is the fastest-growing stream.

Deeply: the same Eucharist is celebrated in Gothic cathedrals, storefront churches, and open-air African revivals; the music runs from Byzantine chant to gospel choirs to Pentecostal praise. Christianity has always translated itself — it has no single sacred language — which is how its center of gravity could shift to the Global South.

Authority (pope, tradition, or Scripture alone); how the sacraments work; infant versus believer's baptism; predestination versus free will; women's ordination; sexuality and marriage; and how literally to read Genesis. The divisions of 1054 and 1517 remain unhealed, though the 20th-century ecumenical movement narrowed some gaps.

Some rest on misunderstanding: that the Trinity means three gods (the creeds insist on one God), or that faith opposes reason (the university itself is a church invention). Others are real disagreements: the problem of evil, the justice of hell, the exclusivity of salvation through Christ, and the church's historical record — each argued seriously inside Christianity as well as against it.

Baptism confers an identity said to run deeper than nation or class — 'neither Jew nor Greek… all one in Christ' (Galatians 3:28). The week is shaped by Sunday and the year by Christmas and Easter, and the community expects visible charity: the early church grew partly because it nursed the sick and fed the poor beyond its own membership.

Mainstream churches teach that science and faith answer different questions: the Catholic Church accepts evolution and runs its own observatory, and pioneers of science — Kepler, Newton, Mendel, Lemaître — were believers. Real tension persists in some Protestant circles over evolution and biblical criticism, and everywhere over secular ethics; each community negotiates its own line.

The New Testament prescribes no form of state: Jesus separated the coin of Caesar from the things of God (Mark 12:17), and Augustine framed history as two cities — earthly and heavenly — never to be confused. Christians have accordingly lived under and built every arrangement, from Christendom's church-state fusion to modern democracy, whose ideas of conscience and human dignity many trace partly to Christian roots. Civil law is judged by God's moral law, but civil rule is not clergy rule.

Power stands under God and is therefore limited: rulers are owed honor (Romans 13:1–7), but 'we must obey God rather than men' (Acts 5:29). On the next step Christians split — from patient endurance, to the Reformers' right of lesser magistrates to resist a tyrant, to Martin Luther King's nonviolent disobedience, arguing from Augustine and Aquinas that an unjust law is no law at all.

Equal in creation and salvation: both made in God's image (Genesis 1:27), 'neither male nor female… in Christ' (Galatians 3:28) — while roles are contested. Traditional readings (Catholic, Orthodox, many evangelicals) reserve ordination to men and speak of male headship in marriage (Ephesians 5); egalitarian Protestants ordain women and read those texts as tied to their era. Historians credit early Christianity with raising women's standing in the ancient world, even as the churches long excluded women from office.

Jesus commanded love of enemies and never coerced belief — when a village refused him, he simply moved on (Luke 9:52–56). The record afterward is mixed: the persecuted early church pleaded for tolerance, but state Christianity later punished heresy and pressured Jews and pagans. Today virtually all churches affirm religious freedom — Vatican II declared coerced faith worthless — and Christians live peaceably as minorities across the world.

Never to spread the faith: 'my kingdom is not of this world,' Jesus told Pilate — 'otherwise my servants would fight' (John 18:36). Beyond that, two traditions: pacifism (the early church and today's Anabaptists refuse all violence) and the just-war doctrine of Augustine and Aquinas — force only by lawful authority, for a just cause such as defense, as a last resort, and with restraint. The Crusades' idea of holy war is rejected by essentially every church today.

The New Testament assigns no earthly penalty for leaving: apostasy is warned against as spiritual loss (Hebrews 6:4–6), and the prescribed response is grief and prayer for return. For centuries, however, Christian states did punish apostasy and heresy by law — from the Theodosian Code to the Inquisition. Modern Christianity has renounced this: leaving can carry social cost in tight communities, but every major church today affirms the freedom to walk away.

The resurrection argument: most historians grant that Jesus was crucified, that his tomb was reported empty, and that his followers sincerely believed he appeared to them alive — a conviction preserved in a creed datable to within a few years of the events (1 Corinthians 15:3–8) — and that it turned frightened disciples into martyrs and launched the church. N.T. Wright and Gary Habermas argue the resurrection itself is the best explanation of those facts. Supporting lines: the moral argument that objective good and evil point to God (Lewis), Aquinas' arguments from the world's existence and order, and the faith's demonstrated power to remake lives.

Hume argued that no testimony can establish a miracle, since uniform experience stands against it; Christians answer that this assumes what it must prove, and that the resurrection evidence should be weighed like any historical question. The problem of evil — pressed from Epicurus to J.L. Mackie — asks how a good, almighty God permits suffering; Plantinga's free-will defense is widely credited, even by critics, with answering its logical form, while Lewis admitted pain remains the hardest fact pastorally. Ehrman argues the texts were corrupted in copying and that Jesus' divinity grew late; textual scholars reply that the variants are catalogued and largely recoverable, and Wright and Bauckham find worship of Jesus in the earliest layers.

The pressure points are the Trinity (how is God one and three?) and the Incarnation (how is Christ both God and man?). Christian thinkers answer that these are mysteries, not contradictions: God is one in essence and three in person — one and three in different respects — and the Council of Chalcedon defined Christ as one person in two natures. Analytic philosophers such as Swinburne and Plantinga have defended the formal coherence of both; critics remain unconvinced that 'mystery' is not a polite name for paradox.

In history: Jesus' life and crucifixion are among the best-attested facts of antiquity — pagan and Jewish sources included — and the church's explosive rise is undisputed, while archaeologists debate some early Old Testament events such as the Exodus. In science: mainstream Christianity accepts cosmology and evolution as the account of how God creates, though literalist readings collide with both. In experience: Christians argue their diagnosis fits the human data — dignity and wickedness together; Chesterton called original sin the only part of Christian theology that can really be proved.

Christians themselves answer no — not in full: the Sermon on the Mount sets a standard ('be perfect,' Matthew 5:48) that the tradition says no one but Christ has met, which is why the whole system runs on grace rather than achievement (Romans 7 is Paul's own confession of falling short). The tension shows in public life: no Christian society has governed by 'turn the other cheek,' borrowing instead from Roman law and secular statecraft — Niebuhr made this candor famous. Defenders reply that the ethic was given to disciples, not legislatures, and that the saints show the life is livable in substance if never in perfection.

Achievements: the hospital and the university are church inventions; Christians led the abolition of the slave trade (Wilberforce, driven openly by faith), built much of the West's charitable infrastructure, and shaped its art, music, and human-rights language. Harms done in its name: the Crusades, the Inquisitions, Europe's wars of religion, centuries of Christian antisemitism that helped prepare the ground for the Holocaust, and missions entangled with colonial conquest and abuses such as the residential schools. Christians answer that these betrayed Jesus' explicit teaching rather than applied it, that the loudest critics of church crimes were usually other Christians, and that the churches have formally repented — John Paul II's public apologies of 2000 being the most sweeping. Critics reply that institutions ruling in Christ's name did these things for centuries, and the record must keep both columns.

Christianity states its own test: Paul wrote that 'if Christ has not been raised, our preaching is useless and so is your faith' (1 Corinthians 15:14) — so showing that Jesus stayed dead, or never lived, would end the claim. Philosophers add others: a proof that the concept of God is incoherent, or that evil is logically incompatible with him. Since the resurrection cannot now be replayed, critics note the test is historical rather than experimental; believers answer that a faith staking everything on one public, investigable event is more falsifiable than most.