Belief in one God
Christianity is a monotheistic religion. Christians worship the God of Abraham, Isaac and Jacob known from the Hebrew Bible, whom they understand as creator of all things, holy, just and loving.
Most Christians express their understanding of God through the doctrine of the Trinity: one God in three persons, Father, Son and Holy Spirit. The Trinity is not understood as three gods but as one divine being who exists eternally in three distinct persons. Some groups that identify as Christian, such as Unitarians, Jehovah’s Witnesses and Latter-day Saints, reject or redefine this doctrine, and are therefore outside the definition used by the historic creeds.
Belief about Jesus Christ
Jesus is at the center of Christian belief. Christians believe that he is the Messiah, or Christ, promised in the Hebrew scriptures, and that he is fully God and fully human. This belief is called the incarnation.
The Gospels describe his teaching, miracles, death by crucifixion under the Roman governor Pontius Pilate, and resurrection on the third day. Christians believe his death and resurrection are the decisive events through which God deals with sin and death. The resurrection is foundational: the apostle Paul wrote that if Christ has not been raised, Christian faith is in vain.
Belief in the Holy Spirit
Christians believe that the Holy Spirit is God present and active in the world and in believers. The Spirit is associated with creation, the inspiration of the prophets, Jesus’ ministry and the life of the Church after Pentecost.
Christians describe the Spirit as guiding, comforting, giving spiritual gifts and transforming believers to become more like Christ. Pentecostal and charismatic Christians place special emphasis on the Spirit’s gifts in worship.
Scripture and the Bible
The Bible is the sacred scripture of Christianity. It includes the Old Testament, which largely corresponds to the Hebrew Bible, and the New Testament, which contains the Gospels, Acts, letters and Revelation.
Christians differ on the exact canon. Catholic and Orthodox Bibles include books, sometimes called deuterocanonical, that most Protestant Bibles do not. They also differ on authority: Protestants generally stress scripture as the final authority, while Catholic and Orthodox Christians understand scripture within the living tradition of the Church.
Creation, humanity and sin
Christians believe that God created the world good and created human beings in his image. Humanity is understood to have turned away from God, an event and condition often called the fall, so that sin affects every person and the world.
Christian traditions describe the effects of sin differently. Western traditions often speak of original sin, while Eastern Orthodox teaching emphasizes the inherited condition of mortality and corruption rather than inherited guilt.
Salvation
Christians believe that salvation is God’s gift through Jesus Christ. Through his life, death and resurrection, people can be forgiven, reconciled to God and given new life.
How salvation is received is one of the major areas of Christian disagreement. Protestant traditions often stress justification by grace through faith. Catholic teaching emphasizes grace received through faith and the sacraments, working through love. Orthodox Christianity often describes salvation as theosis, a lifelong process of being united with God.
Resurrection and future hope
Christians believe that Christ will return, that the dead will be raised and that God will judge the world and make all things new. The Nicene Creed confesses belief in “the resurrection of the dead and the life of the world to come.”
Christian hope is not only about individual souls going to heaven. Many Christians emphasize the renewal of creation, the bodily resurrection and the final victory of God’s justice and love.
The Church and Christian community
Christians believe that the Church is the community of those who belong to Christ, sometimes described as the body of Christ. Most Christians practise baptism as the rite of entry into the Church and celebrate the Eucharist, also called Holy Communion or the Lord’s Supper.
The three largest branches are Catholic, Orthodox and Protestant Christianity, with Oriental Orthodox, Anglican and many independent churches adding to the picture. They differ on church structure, the number and meaning of sacraments, and the role of bishops and the Pope.
How much do Christians agree with one another?
Despite real differences, most Christians share a recognizable core: one God as Trinity, Jesus as Son of God and Savior, his death and resurrection, the authority of scripture, baptism, and hope in the resurrection. The Nicene Creed, completed in the fourth century, is accepted by Catholic, Orthodox and most Protestant churches.
Disagreements arise over authority, sacraments, salvation, ethics and church governance. These differences are why a summary of Christian belief should name which tradition it describes when it moves beyond the shared core.
A concise answer
Christians believe in one God who is Father, Son and Holy Spirit; that Jesus Christ is God made human, who died and rose again to save people from sin and death; that the Bible is sacred scripture; and that God will one day raise the dead and renew creation. Catholic, Orthodox and Protestant Christians share this core but differ on church authority, sacraments and how salvation is received.