Christianity is an Abrahamic monotheistic religion based on the life and teachings of Jesus Christ as presented in the New Testament. Christianity is the world's largest religion, with about 2.4 billion adherents, known as Christians. Christians believe that Jesus is the Son of God, fully divine and fully human, and the savior of humanity whose coming as Christ or the Messiah was prophesied in the Old Testament.

Christianity began as a Second Temple Judaic sect in the mid-1st century. Originating in the Middle East, it quickly spread to Europe, Syria, Mesopotamia, Asia Minor and Egypt and by the end of the 4th century had become the official state church of the Roman Empire. Following the Age of Discovery, Christianity spread to the Americas, Australasia, sub-Saharan Africa, and the rest of the world through missionary work and colonization. Christianity has played a prominent role in the shaping of Western civilization.
Worldwide, the three largest branches of Christianity are the Catholic Church, the Eastern Orthodox Church and the various denominations of Protestantism. The Roman Catholic and Eastern Orthodox patriarchates split from one another in the schism of the 11th century; Protestantism came into existence in the Reformation of the 16th century, splitting from the Roman Catholic Church.

Beliefs
Christians share a certain set of beliefs that they hold as essential to their faith, though there are many important differences of interpretation and opinion of the Bible on which Christianity is based.

Creeds

Concise doctrinal statements or confessions of religious beliefs are known as creeds (from Latin credo, meaning "I believe"). They began as baptismal formulae and were later expanded during the Christological controversies of the 4th and 5th centuries to become statements of faith.
Many evangelical Protestants reject creeds as definitive statements of faith, even while agreeing with some or all of the substance of the creeds. The Baptists have been non-creedal "in that they have not sought to establish binding authoritative confessions of faith on one another."[25]:p.111 Also rejecting creeds are groups with roots in the Restoration Movement, such as the Christian Church (Disciples of Christ), the Evangelical Christian Church in Canada and the Churches of Christ.
An Eastern Christian icon depicting Emperor Constantine and the Fathers of the First Council of Nicaea (325) as holding the Niceno–Constantinopolitan Creed of 381.
The Apostles' Creed remains the most popular statement of the articles of Christian faith which are generally acceptable to most Christian denominations that are creedal. It is widely used by a number of Christian denominations for both liturgical and catechetical purposes, most visibly by liturgical Churches of Western Christian tradition, including the Latin Church of the Catholic Church, Lutheranism, Anglicanism, and Western Rite Orthodoxy. It is also used by Presbyterians, Methodists, and Congregationalists. This particular creed was developed between the 2nd and 9th centuries. Its central doctrines are those of the Trinity and God the Creator. Each of the doctrines found in this creed can be traced to statements current in the apostolic period. The creed was apparently used as a summary of Christian doctrine for baptismal candidates in the churches of Rome.

Its main points include:
    belief in God the Father, Jesus Christ as the Son of God and the Holy Spirit
    the death, descent into hell, resurrection, and ascension of Christ
    the holiness of the Church and the communion of saints
    Christ's second coming, the Day of Judgement and salvation of the faithful.

Ten Commandments
The Ten Commandments are a set of biblical principles relating to ethics and worship which play a fundamental role in Judaism and most forms of Christianity. They include instructions to worship only God and to keep the Sabbath, and prohibitions against idolatry, blasphemy, murder, theft, and adultery. Different groups follow slightly different traditions for interpreting and numbering them. According to the synoptic gospels, Christ generalised the law into two underlying principles; The first is "Hear, O Israel: The Lord our God, the Lord is one; and you shall love the Lord your God with all your heart, and with all your soul, and with all your mind, and with all your strength." While the second is "You shall love your neighbor as yourself."
These are quotes from Deuteronomy 6:4 and Leviticus 19:18. Barnes' Notes on the New Testament comments on these verses saying: "These comprehend the substance of what Moses in the law, and what the prophets have spoken. What they have said has been to endeavour to win men to the love of God and each other. Love to God and man comprehends the whole [of] religion; and to produce this has been the design of Moses, the prophets, the Saviour, and the apostles."

Jesus
The central tenet of Christianity is the belief in Jesus as the Son of God and the Messiah (Christ). Christians believe that Jesus, as the Messiah, was anointed by God as savior of humanity, and hold that Jesus' coming was the fulfillment of messianic prophecies of the Old Testament. The Christian concept of the Messiah differs significantly from the contemporary Jewish concept. The core Christian belief is that through belief in and acceptance of the death and resurrection of Jesus, sinful humans can be reconciled to God and thereby are offered salvation and the promise of eternal life.

Death and Resurrection
Christians consider the resurrection of Jesus to be the cornerstone of their faith and the most important event in history. Among Christian beliefs, the death and resurrection of Jesus are two core events on which much of Christian doctrine and theology is based. According to the New Testament Jesus was crucified, died a physical death, was buried within a tomb, and rose from the dead three days later.

Salvation
Paul the Apostle, like Jews and Roman pagans of his time, believed that sacrifice can bring about new kinship ties, purity, and eternal life. For Paul the necessary sacrifice was the death of Jesus: Gentiles who are "Christ's" are, like Israel, descendants of Abraham and "heirs according to the promise". The God who raised Jesus from the dead would also give new life to the "mortal bodies" of Gentile Christians, who had become with Israel the "children of God" and were therefore no longer "in the flesh".

Trinity
Trinity refers to the teaching that the one God comprises three distinct, eternally co-existing persons; the Father, the Son (incarnate in Jesus Christ), and the Holy Spirit. Together, these three persons are sometimes called the Godhead, although there is no single term in use in Scripture to denote the unified Godhead. In the words of the Athanasian Creed, an early statement of Christian belief, "the Father is God, the Son is God, and the Holy Spirit is God, and yet there are not three Gods but one God". They are distinct from another: the Father has no source, the Son is begotten of the Father, and the Spirit proceeds from the Father. Though distinct, the three persons cannot be divided from one another in being or in operation.

Scriptures
Christianity, like other religions, has adherents whose beliefs and biblical interpretations vary. Christianity regards the biblical canon, the Old Testament and the New Testament, as the inspired word of God. The traditional view of inspiration is that God worked through human authors so that what they produced was what God wished to communicate. The Greek word referring to inspiration in 2 Timothy 3:16 is theopneustos, which literally means "God-breathed".

Death and Afterlife
Most Christians believe that human beings experience divine judgment and are rewarded either with eternal life or eternal damnation. This includes the general judgement at the resurrection of the dead as well as the belief (held by Roman Catholics, Orthodox and most Protestants) in a judgment particular to the individual soul upon physical death.

Symbols
Christianity has not generally practiced aniconism, or the avoidance or prohibition of types of images, even if the early Jewish Christians sects, as well as some modern denominations, preferred to some extent not to use figures in their symbols, by invoking the Decalogue's prohibition of idolatry.
The cross, which is today one of the most widely recognized symbols in the world, was used as a Christian symbol from the earliest times. Tertullian, in his book De Corona, tells how it was already a tradition for Christians to trace repeatedly on their foreheads the sign of the cross. Although the cross was known to the early Christians, the crucifix did not appear in use until the 5th century.

Prayer
Jesus' teaching on prayer in the Sermon on the Mount displays a distinct lack of interest in the external aspects of prayer. A concern with the techniques of prayer is condemned as 'pagan', and instead a simple trust in God's fatherly goodness is encouraged. Elsewhere in the New Testament this same freedom of access to God is also emphasized. This confident position should be understood in light of Christian belief in the unique relationship between the believer and Christ through the indwelling of the Holy Spirit.

Christian Culture
Western culture, throughout most of its history, has been nearly equivalent to Christian culture, and many of the population of the Western hemisphere could broadly be described as cultural Christians. Though Western culture contained several polytheistic religions during its early years under the Greek and Roman empires, as the centralized Roman power waned, the dominance of the Catholic Church was the only consistent force in Europe. Until the Age of Enlightenment, Christian culture guided the course of philosophy, literature, art, music and science. Christian disciplines of the respective arts have subsequently developed into Christian philosophy, Christian art, Christian music, Christian literature etc.

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Christianity - Wikipedia, the free encyclopedia: Christianity is the world's largest religion, with about 2.4 billion adherents, [note 2] known as Christians. Christians believe that Jesus is the Son of God, fully divine and fully human, and the savior of humanity whose coming as Christ or the Messiah was prophesied in the Old Testament.

BBC - Religion - Christianity: Christianity is the world's biggest religion, with about 2.1 billion followers worldwide. It is based on the teachings of Jesus Christ who lived in the Holy Land 2,000 years ago.

Christianity - Faith in God, Jesus Christ: Learn about Christianity - having faith in God and Jesus Christ. Christian living articles, daily devotionals, Bible trivia, and more!

Christianity - ReligionFacts: Christianity has historically taken correct doctrine very seriously. The early fathers and church councils carefully distinguished between "orthodoxy" from "heresy" ...

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