Short answer
- A Christian is a person who follows Jesus Christ and identifies with the Christian faith. In Christian teaching, that means trusting in Jesus as the Son of God and Savior, accepting his death and resurrection as the way to forgiveness and new life, and living as part of his people, the church. The word comes from the Greek word for Christ, meaning anointed one, and it was first used for Jesus followers in Antioch, according to the New Testament book of Acts. Christians share that focus on Jesus, but they belong to many traditions, including Catholic, Eastern Orthodox, Oriental Orthodox, and Protestant churches, and they differ on church authority, the sacraments, and interpretation of the Bible. There is no single worldwide office that decides who counts as a Christian, so counts of Christians depend on whether the test used is baptism, personal belief, or self-identification.
By Emma Hudson
The word Christian appears on census forms, in news reports, in church names, and in everyday speech. Sometimes it means a set of beliefs, sometimes a cultural background, and sometimes simply a person who goes to church at Christmas and Easter. This article explains the term in plain language: where it came from, what Christians commonly believe, how they worship, and how the major traditions differ. Where Christians disagree, it attributes each view to the tradition that holds it, rather than presenting one tradition’s view as the view of all Christians.
What the word Christian means
The word Christian comes from the Greek word Christianos, built on Christos, the Greek translation of the Hebrew word Messiah. Both words mean anointed one. In the ancient world, anointing with oil marked a person chosen for a special role, such as a king or a priest. Christians use the title Christ for Jesus of Nazareth because they believe he is the promised Messiah, sent by God to save humanity.
The New Testament uses the word Christian only three times. The first use is in Acts 11:26, which says that the disciples were first called Christians in Antioch, a large, mixed city in the Roman province of Syria whose Christian community included both Jews and non-Jews. Scholars generally explain the name as one given by outsiders, not invented by believers themselves, following a pattern for followers of a leader: just as followers of Herod could be called Herodians, followers of Christ were called Christians. Before that label caught on, Jesus followers called themselves disciples, believers, brothers and sisters, saints, and followers of the Way, a name in Acts pointing to Jesus as the way to God. In its oldest sense, then, a Christian is a person identified with Christ, not primarily a person belonging to a particular building, nation, or denomination.
Who Jesus is in Christian belief
Christianity, as Encyclopedia Britannica puts it, is the faith tradition that focuses on the figure of Jesus Christ. Christians believe that Jesus, born in Bethlehem and raised in Nazareth in the first century CE, is the Son of God who became human, taught about the kingdom of God, was crucified under the Roman governor Pontius Pilate, rose from the dead, and will return at the end of history to judge the living and the dead. That summary is drawn from the Nicene Creed, a fourth century statement of faith still used by many Catholic, Orthodox, and Protestant churches, and it is a useful shorthand for mainstream belief. It is not accepted in exactly the same form by every group calling itself Christian, as the section on the Trinity explains.
In Christian teaching, Jesus is both fully human and fully divine, a doctrine called the incarnation, from the Latin word for becoming flesh. Christians believe that in Jesus, God entered human life directly, and that Jesus is the definitive revelation of God. Jesus is also called Savior, because Christians believe he rescues people from sin and death, and Lord, because they believe he has authority over the church and, in the end, over all creation.
Attribution matters here. These are claims of Christian faith, not facts established by historical research in the same way as a date or a place. Historians can establish that a first century Jewish teacher named Jesus lived, taught in Galilee and Judaea, and was executed by crucifixion. Whether he rose from the dead, and whether he is divine, are matters of faith on which Christians and non Christians differ. This article reports what Christians believe; it does not ask the reader to accept those beliefs.
Core beliefs most Christians share
One God. Christians are monotheists. They believe in one God, creator of heaven and earth, who is also the God of Abraham, Isaac, and Jacob in the Hebrew Bible. Christianity grew out of Judaism, and it has consistently rejected polytheism, belief in many gods, while seeking to remain faithful to the experience of one God.
The Trinity. Most Christians understand the one God as Trinity: Father, Son, and Holy Spirit, three persons in one Godhead. The word Trinity does not appear in the New Testament, and the doctrine was worked out over several centuries of debate. Britannica calls it one of the central Christian affirmations about God, rooted in the way God is presented in the New Testament as Father, as Jesus Christ, and as the Holy Spirit. Not all groups that identify as Christian accept it. Classical Unitarians, Jehovah’s Witnesses, and some other groups understand God as one person only and Jesus as subordinate or created, not as God in the Trinitarian sense. Mainstream Catholic, Orthodox, and Protestant churches regard Trinitarian belief as essential; those minority groups regard it as a later error. This article reports both positions without deciding between them.
Creation, sin, and salvation. Christians believe God created the world and that it is good, that human beings are made in the image of God, and that human beings have turned away from God, a condition called sin, damaging relationships with God, other people, and creation. With rare exceptions, Christians believe human beings need rescue, and Jesus is the agent of that rescue: his death on the cross atones for sin, dealing with its guilt and power, and his resurrection defeats death and opens the way to eternal life. Christians differ on how the cross works, and on the roles of faith, good works, and sacraments in salvation, but they agree salvation comes through Jesus, not through human effort alone.
The Holy Spirit and life after death. Christians believe the Holy Spirit is God active in the world and the church, giving new life and guiding believers into truth. In the New Testament, the Spirit descends on the disciples at Pentecost, fifty days after Easter, an event celebrated as the birth of the church’s public mission. Christians also believe Jesus rose bodily from the dead, believers who die will also be raised, and history will end with final judgment and a renewed creation. Traditions describe judgment and any intermediate state differently: Catholics teach purgatory, purification after death, while most Protestants and Orthodox Christians do not teach it in the same form.
Love of God and neighbor. Christians believe faith must show itself in love. Jesus summarized the law, in the Gospels, as loving God with all one’s heart, soul, and mind, and loving one’s neighbor as oneself. Ethical teaching therefore matters in every tradition, even though traditions differ on specific moral questions, such as divorce, contraception, same-sex relationships, and the use of force, and individual Christians often disagree with their own churches on those questions.
The Bible: the Christian scriptures
The Bible has two parts. The Old Testament tells the story of Israel, from creation through the patriarchs, the exodus from Egypt, the kings, the prophets, and the exile, in law, history, poetry, and prophecy. Christians read it as the Hebrew Bible, shared in large part with Judaism, but in the light of Jesus, whom they believe it points toward. The New Testament contains the four Gospels, telling the story of Jesus, the book of Acts, telling the story of the early church, letters to early Christian communities, and the book of Revelation.
Christians regard the Bible as inspired by God, but they differ on what inspiration means. Some read it literally, as fully accurate in every historical and scientific detail. Others read it as authoritative for faith and practice while accepting that its human authors used the literary forms and knowledge of their own times. Most churches fall between those poles, and the difference shapes debates about creation, gender roles, and social ethics.
Christians also differ on which books belong in the Bible. The New Testament is the same across the major traditions, but the Old Testament is not. Catholic Bibles include additional books, often called deuterocanonical books, such as Tobit, Judith, and 1 and 2 Maccabees, which Protestant Bibles generally place in a separate section called the Apocrypha or omit. Orthodox Bibles include a somewhat larger collection again. For most Christians, the Bible is read in worship, preached from on Sundays, studied in small groups, and used for personal prayer, usually in translation, since few Christians read Hebrew and Greek.
Worship and everyday practice
Christian worship ranges from a quiet Quaker meeting with no set liturgy to a Roman Catholic Mass with incense, chant, and vestments, to a Pentecostal service with contemporary music and spontaneous prayer. Several practices recur across traditions.
Prayer and Sunday worship. Christians pray privately and together, in set words and free speech, in silence and song. The Lord’s Prayer, taught by Jesus in the Gospels, is used across almost all traditions. Most Christians gather on Sunday, the day on which they believe Jesus rose from the dead, for readings, a sermon or homily, hymns or songs, prayers, and, in many churches, the Eucharist. Some, notably Seventh-day Adventists, worship on Saturday, the Jewish Sabbath, instead.
Baptism. Baptism is the rite of entry into the Christian community, involving water and, in most traditions, the words “in the name of the Father, and of the Son, and of the Holy Spirit.” Catholics and Orthodox Christians baptize infants, understanding baptism as God’s gift received before a person can respond. Many Baptist and Pentecostal churches baptize only adults or older children who profess faith, by full immersion. Orthodox baptism is normally by triple immersion, followed immediately by chrismation, anointing with consecrated oil. These differences reflect different understandings of faith and grace, not mere taste.
The Eucharist. The Eucharist, also called Holy Communion or the Lord’s Supper, is the meal in which Christians share bread and wine in memory of the Last Supper, a central act of worship in most churches, in Britannica’s words. What the bread and wine are understood to be is a major difference. Catholics teach transubstantiation, the change of bread and wine into the body and blood of Christ while their outward appearances remain. Orthodox Christians affirm a real presence of Christ without defining the change in Catholic philosophical terms. Lutherans affirm Christ’s real presence in, with, and under the bread and wine. Many Baptist churches understand the meal primarily as a memorial, while Reformed churches generally affirm a spiritual presence of Christ in the meal. Some groups, such as the Religious Society of Friends, do not observe it at all.
The church year and daily life. Most churches follow a calendar built around Jesus: Advent prepares for Christmas, his birth; Lent, forty days of fasting and reflection, prepares for Holy Week and Easter, his resurrection; Pentecost follows Easter. Beyond Sunday, practice includes personal prayer and Bible reading, giving to church and charity, fasting in some traditions, pilgrimage in others, and service to neighbors. Monastic communities of monks and nuns, prominent in Catholic and Orthodox traditions, devote their lives to prayer and work under vows of poverty, chastity, and obedience.
How a person becomes a Christian
There is no single worldwide test, and the answer depends on who is asking. In church terms, a person becomes a Christian through baptism and profession of faith: a baptized infant in a Catholic or Orthodox church is counted from baptism onward, while an adult baptized in a Baptist church is counted after professing faith and being immersed. In theological terms, many Protestants emphasize personal faith: a Christian is someone who trusts in Jesus for salvation, repents of sin, and commits to following him, with baptism expressing faith rather than replacing it. In survey terms, a Christian is someone who says they are one. When Pew Research Center counts Christians, it counts people who identify as Christian in censuses and surveys, which includes cultural Christians who rarely attend church. None of these methods is wrong; they answer different questions, and a reader comparing figures should check which method was used. A person can also be culturally Christian, raised in a Christian family or country and shaped by its customs, without holding Christian beliefs, and can hold Christian beliefs without belonging to any church.
The major Christian traditions
Britannica names the largest groups as the Roman Catholic Church, the Eastern Orthodox churches, and the Protestant churches, with the Oriental Orthodox churches as one of the oldest branches. Each understands itself as faithful to Jesus and the apostles, and each regards the others as mistaken on at least some points. Each also contains wide internal variety.
Roman Catholic. The Roman Catholic Church is the largest Christian group in the world, a single worldwide church under the pope, the bishop of Rome, whom Catholics regard as successor of the apostle Peter and visible head of the church on earth. Catholics recognize seven sacraments: baptism, confirmation, Eucharist, reconciliation, anointing of the sick, holy orders, and matrimony, and worship centers on the Mass. Catholics honor Mary and the saints, asking for their prayers, which Catholics understand as asking fellow church members, living and dead, to pray for them, not as worship of Mary or the saints. Catholic teaching is guided by Bible and church tradition, interpreted by the magisterium, the church’s teaching authority.
Eastern Orthodox. The Eastern Orthodox churches are a communion of self-governing national churches, including those of Constantinople, Russia, Greece, Romania, Serbia, and others. The Ecumenical Patriarch of Constantinople is honored as first among equals, but without the universal jurisdiction Catholics attribute to the pope. Worship centers on the Divine Liturgy, with icons, chant, and incense. Orthodox Christians generally recognize seven holy mysteries in recent centuries, and baptize by immersion, followed by chrismation and first communion, even for infants. They separated from the Western church in the Great Schism, traditionally dated to 1054, over papal authority and the wording of the Nicene Creed, including whether the Holy Spirit proceeds from the Father alone, the Orthodox position, or from the Father and the Son, the Western addition known as the Filioque.
Oriental Orthodox. The Oriental Orthodox churches, including the Coptic Orthodox Church of Egypt, the Ethiopian Orthodox Church, the Armenian Apostolic Church, and the Syriac Orthodox Church, are among the oldest Christian communities. They separated from the rest of the church in the fifth century over Christology, the doctrine of Christ’s nature. Oriental Orthodox Christians affirm Christ as fully divine and fully human united in one nature, while Eastern Orthodox and Catholic Christians express the same conviction as two natures in one person. Modern dialogue has found the difference is often one of language, but the churches remain separate.
Protestant. Protestantism began as a reform movement in Western Christianity in the sixteenth century. Martin Luther circulated his Ninety-five Theses in 1517, challenging the sale of indulgences and, in time, papal authority and Catholic teaching on salvation. Huldrych Zwingli and John Calvin carried reform further, and the Church of England separated from Rome under Henry VIII in the 1530s. Protestant churches are therefore many: Lutherans, Anglicans, Reformed and Presbyterian churches, Baptists, Methodists, and Pentecostals differ widely. Most recognize only two sacraments, baptism and the Eucharist, as instituted by Christ in the Gospels, and most emphasize the Bible above tradition, sola scriptura, scripture alone, and salvation by faith alone, sola fide. Pentecostal and charismatic churches, among the fastest growing movements, emphasize gifts of the Holy Spirit, including speaking in tongues and healing.
Other groups. Many independent churches, especially in Africa, Asia, and Latin America, fit none of the older categories neatly. Groups whose Christian identity is disputed by mainstream churches, including Jehovah’s Witnesses and the Church of Jesus Christ of Latter-day Saints, use the Bible and speak of Jesus but reject the Trinity and other mainstream doctrines, and mainstream churches generally do not recognize their baptisms in the same way. Whether they should be called Christian is contested, and this article notes the dispute rather than resolving it.
Christianity around the world today
Pew Research Center, in its 2025 report on how the global religious landscape changed from 2010 to 2020, estimated Christians at about 2.3 billion in 2020, up from about 2.1 billion in 2010, but down as a share of world population from about 31 percent to about 29 percent, because the rest of the world grew faster. Christians remained the world’s largest religious group in 2020, ahead of Muslims at about 2.0 billion. Sub-Saharan Africa had passed Europe as the region with the most Christians, with about 697 million in sub-Saharan Africa in 2020, compared with about 505 million in Europe and about 238 million in North America. The center of gravity of world Christianity has thus moved south, even though the faith began in the Middle East and was long centered in Europe. Later figures will differ by source and method, so a reader should check the year and counting method behind any headline total. In the United States and much of Europe, the Christian share has fallen as people leave the faith in which they were raised, while numbers have grown in sub-Saharan Africa and parts of Asia and Latin America, through birth rates, conversion, and Pentecostal and independent churches.
Christians and other faiths
Christianity shares roots with Judaism: Jews and Christians share the Hebrew Bible, though Jews do not accept Jesus as Messiah or divine, and Christians read those scriptures as pointing to Jesus. The relationship has included centuries of persecution of Jews by Christians, a history mainstream churches have in modern times acknowledged and repented of, as well as cooperation and dialogue. Muslims revere Jesus as a prophet and Messiah, born of the Virgin Mary, but do not believe he is divine or was crucified in the manner Christians affirm; Christians, in turn, do not accept Muhammad as a prophet or the Quran as scripture. The faiths agree on monotheism and many ethical teachings, and disagree fundamentally on the identity of Jesus. Christian teaching on other religions also varies: some Christians hold salvation is found only through explicit faith in Jesus, while others hold God’s grace may reach people beyond the visible church in ways known to God alone.
What a Christian is not
A Christian is not the same as a Catholic, though Catholics are Christians: Catholic is one kind of Christian, as Lutheran, Orthodox, and Baptist are others, so “Christians and Catholics” as two separate religions is a mistake. A Christian is not automatically a weekly churchgoer, and a churchgoer is not automatically a Christian in the faith sense: attendance is a practice, faith is a belief and commitment, and the two can come apart. A Christian is not defined by nationality, ethnicity, or politics, since Christians exist in every ethnic group and country and disagree sharply about politics. Finally, in Christian teaching itself, a Christian is not a person who lives a perfect life, but a person who believes they need forgiveness and are being changed, which is why humility, repentance, and forgiveness are central Christian virtues, even when individual Christians fail to practice them.
A brief note on origins
This article answers what a Christian is. It does not retell the full story of where Christianity began, how it spread through the Roman Empire, and how it became a world religion. That history, including the first-century Jewish context of Jesus, the Jerusalem community, and the spread to non-Jewish converts, is covered in a separate Amberaisle article on where Christianity originated. Readers who want the origins story should read that article alongside this one, and editors should link the two articles when both are live.
Frequently asked questions
What is the difference between a Christian and a Catholic? None of kind. A Catholic is a Christian belonging to the Roman Catholic Church. Protestant and Orthodox Christians are also Christians, in different churches. The confusion comes from everyday speech using Catholic as if it were a separate religion. It is not.
What do Christians believe in simple terms? Christians believe in one God, creator of the world, known as Father, Son, and Holy Spirit. They believe Jesus, the Son, became human, died on the cross for human sin, rose from the dead, and will return to judge the world. They believe the Bible is God’s word for the church, and faith in Jesus brings forgiveness and eternal life. Traditions differ on details, as above.
Do all Christians believe in the Trinity? Most do, including Catholics, Eastern Orthodox, Oriental Orthodox, and mainstream Protestants. Some groups that identify as Christian, including Unitarians and Jehovah’s Witnesses, do not. The Trinity is a majority belief, not one held by every person using the label.
How is a Christian different from a follower of another religion? The distinguishing mark, in Christian self understanding, is the central place of Jesus. Jews do not accept Jesus as Messiah. Muslims accept Jesus as a prophet but not as divine. Other traditions have their own founders, scriptures, and understandings of ultimate reality. A Christian, by definition, centers faith on Jesus as Son of God and Savior.
Can a person be a Christian without going to church? It depends on the test used. Most churches teach Christians should gather with other believers. Some Christians, through illness, isolation, or conscience, do not belong to a local church but still profess faith in Jesus. Survey researchers would count them if they say so; churches might count them differently.
What is the difference between Christian, Protestant, and evangelical? Christian is broadest. Protestant is a family within Christianity, tracing to the sixteenth century Reformation. Evangelical is a movement within Protestantism, and in some countries beyond it, emphasizing personal conversion, Bible authority, and sharing the faith. Not all Protestants are evangelicals.
Is Christianity the largest religion in the world? By Pew Research Center’s 2020 estimates, yes: about 2.3 billion Christians, about 29 percent of world population, ahead of Muslims at about 2.0 billion. The Christian share fell between 2010 and 2020 even as the absolute number rose, because other populations grew faster.
What book do Christians read? The Bible, in its Old Testament and New Testament. Traditions include slightly different books in the Old Testament, as above, but all share the New Testament and the core story of Jesus in the Gospels.
Sources & references
- Encyclopedia Britannica, "Christianity." Opened and read 26 Oct 2026. https://www.britannica.com/topic/Christianity
- Encyclopedia Britannica, "Trinity." Opened and read 26 Oct 2026. https://www.britannica.com/topic/Trinity-Christianity
- Encyclopedia Britannica, "Christianity: The sacraments." Opened via search result 26 Oct 2026. https://www.britannica.com/topic/Christianity/The-sacraments
- Pew Research Center, "How the Global Religious Landscape Changed From 2010 to 2020" (9 Jun 2025), and "Christian population change" summary page. Figures cited are the 2020 estimates in that report. Opened via search result 26 Oct 2026. https://www.pewresearch.org/religion/2025/06/09/christian-population-change/
- United States Conference of Catholic Bishops, "Nicene Creed." Opened via search result 26 Oct 2026. https://www.usccb.org/prayers/nicene-creed
- Church of England, "The Nicene Creed." Opened via search result 26 Oct 2026. https://www.churchofengland.org/node/51615/printable/print
- Encyclopedia Britannica, "Nicene Creed." Opened via search result 26 Oct 2026. https://www.britannica.com/topic/Nicene-Creed
- BiblicalTraining, "Christian" (Acts 11:26 note: disciples first called Christians at Antioch; other early names). Opened via search result 26 Oct 2026. https://www.biblicaltraining.org/library/christian
- Encyclopedia Britannica Kids, "Reformation" (Reformation began in 1517; Luther, Zwingli, Calvin, Henry VIII). Opened via search result 26 Oct 2026. https://kids.britannica.com/kids/article/Reformation/353703
