Christianity is the world's largest religion. It has approximately 2 billion followers. Practiced in virtually every nation on Earth, it is based on the life and teachings of Jesus Christ (4 B.C.?-A.D. 30?). Jesus Christ was a Jewish preacher who is believed to have lived in Palestine (then known by its Roman name, Judea) approximately 2,000 years ago. The word "Christianity" comes from the Greek Christos, a translation of the Hebrew Moshiach, or messiah, meaning the "chosen" or "anointed" one.

Beliefs and Practices

Most Christians belong to one of three groups. They are either Roman Catholic, Protestant, or Eastern Orthodox. The beliefs and practices within each group can vary considerably. But most accept that people are children of God and have immortal souls. Christians believe in one God. This God is a trinity, or a single deity made up of three divine persons. They are the Father (or Creator), the Son (or Word), and the Holy Spirit. Most Christians believe that Jesus Christ, the Son, was the human manifestation of God. They believe Jesus Christ came to Earth, was born of woman, preached, was crucified, and died. They believe that he rose from the dead and ascended into heaven and that through these actions he made it possible for people to be saved from sin.

As an expression of these beliefs, Christianity has various rites (which include sacraments) and rituals. One rite all Christians practice is baptism. Baptism represents one's entry into the community of Christians and also, to some, the washing away of sin. During the baptism ceremony, the body is immersed in water or water is sprinkled on the head. Both children and adults can be baptized.

The Eucharist is another rite practiced by all Christians. Some call the Eucharist Holy Communion or the Lord's Supper. It is the consumption of bread and wine or grape juice, representing Christ's body and blood. It usually takes place during a worship service. According to the Bible, Jesus instituted this sacrament the night before his death. And he instructed his followers to "Do this in remembrance of me." As with baptism, the Eucharist is presided over by a member of the clergy.

Only baptism and the Eucharist are considered sacraments by Protestants. But these and several other rites are considered sacraments by Roman Catholic and Eastern Orthodox churches. They include penance, confirmation (a profession of faith), marriage, extreme unction (last rites for a dying person), and the ordination of clergy.

The Bible is Christianity's most sacred book. It consists of the core religious writings of Judaism, which Christians call the Old Testament, and the New Testament. The New Testament is made up of the Gospels (four "books" detailing the life and teachings of Jesus), the books containing stories of Jesus' immediate followers, the writings of Saint Paul, and the Revelation of Saint John the Divine. The Bible contains scriptures acknowledged by all contemporary Christians. Other significant writings by early Christians — the apocryphal books — are accepted by some Christians and not others.

Nearly all Christians recognize two main holidays, Christmas and Easter. Christmas celebrates Jesus' birth. Easter is the day on which he is believed to have risen from the dead. Good Friday is another important day for many Christians. They believe this is the day on which Jesus was crucified. The Catholic, Anglican (a Protestant sect), and Orthodox churches also celebrate saints' days. And they celebrate holidays such as Ascension Day (forty days after Easter, when Jesus was supposed to have ascended into heaven). Among Protestants, particularly Lutherans, Reformation Sunday (usually the last Sunday in October) marks the beginning of the Protestant Reformation.

Origins and Early History

Christianity emerged during the first century A.D. in Palestine (then known as Judea) as a sect within Judaism. Judea was a province of the Roman Empire. According to the Bible, Jesus preached to the common people that religion was not just something to be practiced by the priests in the Jewish temple. He taught that it was a moral code that should govern all their thoughts and actions. The large crowds that gathered to hear Jesus brought him to the attention of the Roman authorities. The Roman authorities became fearful that Jesus was stirring up the populace against them. So they had Jesus arrested and tried as a political criminal. He was eventually crucified (executed by nailing to a cross).

After the crucifixion, Jesus' followers were inspired by the story of his resurrection. They began to spread his message throughout the empire. In the beginning, this task was largely carried out by his disciples (notably Saint Peter and Saint John), whom Jesus had taught in his lifetime.

Saint Paul, too, played a significant role in promoting the new faith. At first he was among those who persecuted Christians. But later he converted to Christianity. He spent the rest of his life establishing churches and spreading Christ's message.

The early Christians suffered tremendously. Distrusted and hated by many, they were accused of the most vile crimes. Many of their leaders were imprisoned or executed. Persecutions most likely began during the reign of the Roman emperor Nero (37–68). Nero blamed the Christians for setting fire to Rome in A.D. 64.

During the 200's, thousands of Christians were murdered, including Pope Fabian, head of the church in Rome. They refused to offer pagan sacrifices ordered on behalf of Emperor Decius (249–251). Persecutions increased during the first decade of the 300's under Emperor Diocletian (284–305) and his successors.

Despite the persecutions, Christianity spread. In the year 200, the Christian writer Tertullian claimed that Christians lived in almost every town. By the beginning of the 300's it is estimated that nearly half the population of Asia Minor was Christian.

Expansion led to increasing organization of the church. Local congregations or churches were led by pastors called bishops. Under them were ministers of lower rank called presbyters and deacons. All bishops were equal in rank. But those in certain cities, such as Rome, had somewhat more influence.

The Spread of Christianity

The persecutions ended in 313. Constantine (280–337), emperor of the Byzantine Empire (the eastern branch of the Roman Empire), began to favor Christianity. He eventually made it the preferred religion of the empire. He was aided greatly by his Christian mother, Helen. Constantine also supported the observance of Sunday as a Christian holy day. And he financed the construction of the great Christian churches in Rome.

With imperial support, Christianity became more widespread and powerful throughout the Roman Empire, which by then stretched from the Atlantic Ocean to Persia. Under Emperor Theodosius the Great (346?–395), Christianity became the empire's official religion. Thereafter, both paganism and unacceptable forms of Christianity were forbidden.

At this time, however, Christianity still had no formalized body of beliefs, or theology. As individuals presented ideas, conflicts arose. One major conflict resulted from the claim that Jesus was not divine. Formulated by Arius, an Alexandrian priest (250–336), the doctrine known as Arianism became a powerful threat to those who viewed Jesus as wholly divine. It soon developed a large following.

Church leaders considered Arianism a heresy. (A heresy is an opinion that challenges an established belief.) To address this development, a council was held in Nicaea in 325 under the sponsorship of Emperor Constantine. There, the nearly 350 bishops and monastic leaders in attendance rejected Arianism almost unanimously. Despite this rejection, which was also supported by the emperors, Arianism remained a powerful view. It would be condemned again at the second Council of Constantinople in 381.

Over the next 400 years, Christianity formalized its beliefs and rituals. In the East this development was led by theologians Gregory of Nazianzus (329?–389), Gregory of Nyssa (331?–395), Athanasius (293?–373), and John Chrysostom (347–407), who wrote in Greek. In the West, where the Roman Empire collapsed in 476, the theologians known as the Latin Fathers — Jerome (331?–420), Ambrose (339?–397), Gregory the Great (540?–604), and, perhaps most important, Augustine of Hippo (354?–430) — articulated the core beliefs of Christianity.

The growth of Christianity was further aided by the rise of monasteries. (A monastery is a community of men called monks.) Monks live and work together and devote their lives to prayer. The monastic movement began with individuals called hermits, who withdrew to the Egyptian desert to lead solitary lives of prayer. However, it soon developed into a communal form, with groups of monks living together under the direction of an abbot.

Monasteries became an important element within both eastern and western Christianity. This was particularly true of those organized under Saint Benedict (480?–547). They provided some refuge and a place for learning. This was especially important after the western half of the Roman Empire had fallen to Germanic invaders. Also, Saint Benedict had developed a new "rule," a set of regulations governing monastic life. The Rule of Saint Benedict, and the way of life it helped bring about, were the inspiration for much of what was best about Christianity for the next thousand years.

During the Middle Ages (500–1500), the church represented order and control in society. Most people could not read or write, except for priests and monks. And priests were often government officials. Religious faith inspired the creation of countless works of art and architecture. Examples include the magnificent Gothic cathedrals of Chartres, Notre Dame, and Durham. Although it remained in many ways a time of violence, the Middle Ages represented a slow return to civilization following the collapse of the Roman Empire.

It was also during this period, on Christmas Day in 800, that Charlemagne, King of the Franks (742?–814), was crowned the first Holy Roman emperor by Pope Leo III (795–816). This marked the founding of the Holy Roman Empire, a confederation of powerful European states. The influence of this alliance between the pope and Europe's greatest political leader was immense. The church grew even stronger.

Another significant event was the Great Schism. It occurred in 1054 when the Christian church divided into the Eastern and Western branches. This was the result of conflicting beliefs and differences in worship, as well as various political rivalries. The Eastern branch became the Orthodox Church. The Western branch became the Roman Catholic Church.

A century later, during the late Middle Ages, orders (organizations) of friars developed. They preached in the growing cities of Western Europe and served the poor and sick there. The most familiar of these orders are the Franciscans, established by Francis of Assisi (1182–1226), and the Dominicans, established by Saint Dominic (1170–1221). A renewal of learning occurred in the 1200's. This was exemplified by Saint Thomas Aquinas (1225?–74), one of the greatest of all Christian theologians.

The economic and social advances of the late Middle Ages were halted when the bubonic plague swept across Europe from 1347 to 1350. It killed nearly one-third of the population. The plague was also known as the Black Death. It disrupted trade and farming and led to religious excesses, including violent persecution of the Jews.

In the East, Christianity had experienced difficulties since the 600's, as Islam moved westward from the Arabian Peninsula. As Islam expanded, the Byzantine Empire retreated. Constantinople, the empire's capital, was cut off from the West, eventually falling to Muslim invaders in 1453.

The decline of the Christian empire in the East had positive effects for western Europe. The Islamic empires preserved the learning of ancient classical scholars. This body of knowledge, as well as Islamic cultural advances, spread to Europe by way of returning Crusaders, Christian refugees, and traders. The influx of new and ancient ideas helped set the stage for the Renaissance.

The Renaissance began in Italy about 1300 and gradually developed in other European countries. This period, which would last about 300 years, saw a cultural rebirth in Europe. There was a flowering of art, literature, and learning. It was led by such men as Leonardo da Vinci (1452–1519), Michelangelo (1475–1564), and Desiderius Erasmus (1467?–1536). Scholars rediscovered the classical literature and arts of ancient Greece and Rome. The development of the printing press made books (including the Bible) widely available and fostered the spread of new ideas. This atmosphere of free thinking, as well as greater attention to the Bible and the writings of the early church fathers, led people to question certain practices established by the medieval church.

The Reformation to the Modern Era

By the 1500's the church, headquartered in Rome, had become a major power. It was spending huge sums of money on art, buildings, and luxuries for leaders. This money came from taxes people paid on crops or land. It also came from the sale of indulgences. (These were payments believed to release people from punishment for their sins.)

As the church's demands for money increased, professional indulgence sellers wandered throughout Europe. This was widely resented. A growing spirit of nationalism (interest in one's own country) was present throughout much of Europe. Many people were less willing to support the church in Rome.

The Reformation was the movement in which some countries began to break away from Rome. If one could date its beginning to a specific time and place, it would be October 31, 1517. That was when Martin Luther (1483–1546), a German monk and theology professor, posted 95 propositions in Wittenberg, Germany, inviting theological debate on the sale of indulgences.

Luther believed that the whole system of indulgences was wrong. He believed it was contrary to the Bible, especially the writings of Saint Paul. According to Saint Paul, salvation is assured simply by faith in God's love and mercy. Luther soon won numerous German princes to his side. The princes saw the movement as an opportunity to weaken Rome's power over their country. Luther's translation of the Bible into German also helped spread his teachings, as more people could read scripture for the first time.

In 1521, after much debate with papal authorities, Luther was excommunicated from the Catholic Church. (To be excommunicated means to be deprived of the sacraments and the rights of church membership)

Other leaders of the Reformation, or Protestant, movement included Huldreich Zwingli (1484–1531), a pastor in Zurich, Switzerland; John Knox (1513?–72), a Scottish minister who lived in Geneva; and John Calvin (1509–64), a native of Picardy, France. Calvin had escaped to Geneva after being charged with heresy in his home country. He developed a form of Protestantism (Calvinism) that had a great impact on the United States and Europe. (In France, Calvin's followers were called Huguenots.) A major doctrine of Calvinism was that God alone determined the destiny — salvation or damnation — of human souls. Humans could do nothing to save themselves.

In England, the factors leading to the Reformation were more political than religious. King Henry VIII (1491–1547) wished to divorce his wife, Catherine of Aragon. Not only had they failed to produce a male heir, but Henry also wanted to marry Anne Boleyn, a lady of the court. Pope Clement VII refused to grant a divorce. So Henry decided to reject papal authority and make himself head of the English church. Conflict over reform in the English church continued after his death.

Under the boy-king Edward VI (1537–53), greater reforms were adopted. They were only to be undone when Mary I (1516–58) turned back to Catholicism. During the long reign of her successor, Elizabeth I (1533–1603), the Church of England reached a compromise. This resulted in a church (called Anglican or Episcopal) that combined elements of Protestantism and Roman Catholicism. This was possible because no single theologian such as Luther or Calvin ever dominated the English church. In 1611 it also issued the most famous English translation of the Bible. This was the King James Version, which is still widely used today.

The Reformation was successful only in northern Europe. But it made inroads throughout much of the continent at various times. In southern and eastern Europe, however, Catholicism retained its strength. This was largely because the Reformation had led to the Counter, or Catholic, Reformation.

The Counter Reformation was an attempt by individuals within the Catholic Church to reform it and correct abuses. Leading this movement was the Society of Jesus (Jesuits) founded by the Spanish priest and former soldier Saint Ignatius of Loyola (1491–1556). Many of these reforms were formalized by the Council of Trent (1545–63). The Council did much to strengthen Catholicism and to create modern Roman Catholicism.

The Reformation and Counter Reformation sparked years of war, persecution, and violence. During the Thirty Years' War (1618-48), nearly half the population of the German states died from the conflict or from the accompanying famine and disease. When the war ended with the Peace of Westphalia, Europe found itself religiously divided between Catholics and Protestants. Southern Europe — Italy, France, Spain, and Portugal — remained Catholic. Austria, southern Germany, Poland, Slovenia and Croatia, and the Low Countries (present-day Belgium, Luxembourg, and the Netherlands) also did. Protestantism dominated in England, Scotland, northern Germany, northern Holland, the Scandinavian countries, and Bohemia (part of the present-day Czech Republic) and Hungary. In eastern Europe and Greece, the Orthodox Church continued on its course. It was relatively untroubled by events on the rest of the continent.

The religious wars of the 1500's and 1600's helped usher in the Enlightenment. The Enlightenment was a period characterized by fresh views of religion and society. During this time, thinkers such as Montesquieu (1689–1755), John Locke (1632–1704), Wilhelm Leibniz (1646–1716), and others argued that religion was a private matter and not a governmental concern. Others saw the damage that religious wars had inflicted on economies. They argued that religious differences should not interfere with business. Still others asserted that the human mind was created free by God. They said the individual conscience should not, and could not, be coerced. Many rejected the idea that the state should enforce religious conformity according to its ruler's religious views.

The Dutch were among the earliest to accept the notion of religious tolerance, but only informally. Legal measures favoring religious tolerance were first adopted in England. The Church of England would (and still does) remain the state church. But toleration (a government policy of allowing unsanctioned forms of worship and belief) was granted to all Protestants in 1689. Catholics would not receive full religious and political freedom until 1829. This was a remnant of the Reformation-era conflicts.

Meanwhile, conflicts between Catholics and Protestants and between different sects of Protestantism dominated Europe into the 1700's. When Europeans arrived in the New World, Catholicism was the religion of Europe. First European settlements were therefore Catholic. With the Reformation, the New World became a source of conflict between Protestant England and Catholic Spain and France. In British North America, different sects of Protestantism clashed. In New England, the Puritans attempted to create a religiously pure commonwealth, while the Church of England was established in many colonies. New York passed from Swedish to Dutch to British control. It saw its religious establishment change from Lutheranism to Dutch Reformed to the Church of England.

Maryland, established as a haven for Catholics, adopted a policy of toleration for all Christians. This was short-lived, however, and the Church of England was established there in 1702. Of all the colonies, only Pennsylvania and Rhode Island practiced religious tolerance and were without established religions. This changed soon after the creation of the United States. Because the U.S. Constitution guaranteed freedom of religion, religious liberty expanded greatly.

At this time also, the European powers — primarily France, Spain, England, and Portugal — were colonizing other parts of the Western Hemisphere, as well as Africa and parts of Asia. They also introduced Christianity. The Christianization of Asia was relatively unsuccessful, with the exception of the Philippines. But Christianity would become a major religion in much of Africa.

Christianity Today

During the 1900's, increased religious tolerance gave rise to the ecumenical movement. That movement sought to overcome the differences that had splintered Christianity. The movement became stronger after the World Council of Churches was established in 1948 to promote unity among churches. By the year 2000 the council had over 337 member denominations representing over 400 million members on six continents.

Although it did not join the World Council, the Roman Catholic Church responded to the spirit of ecumenism and tolerance at the Second Vatican Council (Vatican II, 1962–65). This council transformed the church's relationship to the modern world. And it acknowledged the need for interreligious discussion and collaboration. Two of its pronouncements, the "Declaration on the Relationship of the Church to Non-Christian Religions" (Nostra Aetate) and the "Declaration on Religious Freedom" (Dignitatis Humanae), altered its opposition to other religious traditions and ended its hostility to religious liberty and church-state separation.

The separation of church and state has freed Christians to become more politically active, often in opposition to government policies. During the 1960's and 1970's, for example, churches played a major role in the civil rights movement. (The civil rights movement was the struggle for equal rights for African Americans.) Toward the end of the 1900's, Christians were at the forefront of the human rights movement. In Poland the Catholic Church played a major role in the fight against Communism.

At the same time, the end of the 1900's saw the rise of a fundamentalist Protestantism. Committed to a literal reading of the Christian Bible, these Christians rejected the theory of evolution, ecumenism, and the scientific view of the universe's creation. In the United States they played a significant role in political affairs. They formed the right wing of the Republican party. Fundamentalist Protestantism also found a niche in Central and South America. There its emphasis on personal morality and hard work found a growing audience among the region's poorest people.

Today, Christianity faces several realities and challenges. The collapse of Communism in Eastern Europe has opened up some countries to new forms of Christianity and has also revitalized their traditional Christian forms. In other countries, particularly Egypt and Sudan, Christianity is encountering a stronger and faster-growing Islam. Whether these religions can peacefully coexist remains an open question.

In Europe, Christianity remains the dominant religion. But fewer Europeans are active churchgoers. Catholicism is no longer Europe's leading Christian faith. But it is dominant in South America, Asia, and Africa. Although most people in the United States are Christian, other religions are growing.

Despite these changes, Christianity continues to play a significant role in the lives of millions.


Edward Queen
Contributor, The Encyclopedia of American Religious History