Saturday, June 20, 2026 · 天火 · tianmu.org

Introduction to Christianity

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A Critical History for the Good Work Library

Christianity is the religion centered on Jesus Christ: his life, teaching, death, resurrection, worship, and continuing presence in the life of the church. It begins as a Jewish apocalyptic and messianic movement under Roman imperial rule and becomes a global tradition of scripture, sacrament, doctrine, prayer, empire, dissent, monasticism, mysticism, reform, mission, colonial entanglement, liberation struggle, and ordinary parish life. Its unity is real. Its divisions are also real.

The Christian tradition is unified by Jesus, the Bible, baptism, eucharistic memory, prayer, and the claim that God acts decisively through Christ for the salvation and transformation of the world. It is divided by canon, creed, church authority, sacrament, Christology, language, empire, reformation, race, colonial history, gender, revival, and modern politics. A serious introduction must resist both slogans: Christianity is neither one uninterrupted institution nor a collection of unrelated denominations. It is a tradition of continuity through conflict.

I. Jesus in the World of Second Temple Judaism

Jesus of Nazareth lived in first-century Galilee and Judea within the world of Second Temple Judaism. His world included Torah, temple, synagogue, purity concerns, Roman taxation, Herodian politics, apocalyptic expectation, Pharisees, Sadducees, scribes, priests, rebels, peasants, healers, prophets, and pilgrims. He was not a generic spiritual teacher floating above history. He was a Jewish teacher and prophet whose message concerned the kingdom of God, repentance, mercy, judgment, healing, forgiveness, table fellowship, and the restoration of Israel.

The Roman Empire matters. Crucifixion was not a neutral death. It was imperial execution, public shame, and terror. To proclaim a crucified man as Messiah and Lord was religiously and politically explosive. Early Christian faith does not begin with a timeless idea of love. It begins with the claim that God raised the executed Jesus from the dead and vindicated him as Lord.

The historian can say with broad confidence that Jesus taught, gathered followers, used parables, performed or was remembered as performing healings and exorcisms, entered conflict with authorities, was crucified under Pontius Pilate, and was proclaimed risen by his followers. The theological meaning of those events is the heart of Christian faith; the historical study of those events is the beginning of Christian origins.

II. Paul, the Gospels, and the First Communities

The earliest surviving Christian writings are not the gospels but the letters of Paul. Paul shows us communities already wrestling with Gentile inclusion, Torah observance, resurrection, spiritual gifts, sexual ethics, food, money, suffering, and the meaning of Christ's death. The early church did not expand beyond Judaism automatically. It argued its way outward through scripture, mission, controversy, and communal practice.

The gospels are theological narratives, not modern biographies. Mark presents a suffering and hidden Messiah. Matthew presents Jesus as teacher, fulfillment of scripture, and authoritative interpreter of Torah. Luke-Acts frames Jesus and the church within salvation history from Israel to the nations. John presents Jesus as the incarnate Logos whose signs reveal divine glory. These differences are not embarrassing accidents. They show that early Christian memory was already interpretive.

Other early Christian writings, including Hebrews, Revelation, the Catholic Epistles, apostolic fathers, apocryphal gospels, martyr acts, and early liturgical fragments, reveal a diverse movement struggling to define authority, worship, ethics, and identity. Yale's Open Courses framing is useful: the New Testament is both scripture for Christians and ancient literature for historical study.

III. Canon, Creed, and Orthodoxy

Christian scripture formed over time. The Old Testament is Israel's scriptures received and interpreted through Christ. The New Testament emerged through apostolic authority, liturgical use, theological suitability, community reception, and boundary-making against rival texts and teachings. The canon was not invented in one meeting. It was recognized, debated, stabilized, and defended across centuries.

Creed developed similarly. Christians worshiped Jesus and invoked the Holy Spirit while confessing one God. This produced the theological pressure that led to Trinitarian doctrine. The councils of Nicaea, Constantinople, Ephesus, and Chalcedon did not create Christian faith from nothing. They defined contested language for communities already baptizing, praying, and reading scripture in Christological form.

Heresy and orthodoxy are not neutral terms. They are categories produced through conflict. Arians, Nicenes, Miaphysites, Nestorians, Gnostics, Marcionites, Montanists, Donatists, Pelagians, and many others show that early Christianity was not simple. The tradition that became orthodox preserved its own memory of those conflicts. A good reader should learn both the doctrinal issues and the power relations that shaped their resolution.

IV. Sacrament, Liturgy, and Embodied Christianity

Christianity is not only belief. It is baptismal and eucharistic. Baptism marks entrance into Christ's death and resurrection, forgiveness, new birth, incorporation into the church, and reception of the Spirit. The Eucharist, Lord's Supper, Mass, or Divine Liturgy gathers Christians around bread and wine as thanksgiving, memorial, sacrifice, communion, real presence, or covenant meal depending on tradition.

The liturgical year shapes time: Advent, Christmas, Epiphany, Lent, Holy Week, Easter, Ascension, Pentecost, saints' days, fasts, and feasts. Christian bodies kneel, stand, cross themselves, sing, fast, receive oil, confess, marry, mourn, process, and bury the dead. Icons, candles, incense, vestments, bells, sermons, psalms, and architecture are not decorative additions. They make theology visible and audible.

Different churches count and understand sacraments differently. Roman Catholic and Orthodox traditions name seven sacraments; many Protestant traditions emphasize baptism and communion while treating other rites differently. These differences are not minor. They express different accounts of grace, church, priesthood, matter, memory, and authority.

V. Empire, Monasticism, and Medieval Christendom

Constantine's patronage and the later Christianization of the Roman Empire changed Christianity permanently. A persecuted minority gained public power, patronage, architecture, councils, legal privilege, and imperial entanglement. This made possible great institutions and also new forms of coercion. The church became capable of shaping society and capable of being shaped by power.

Monasticism emerged as a radical answer to imperial Christianity's comfort. Desert ascetics, Benedictine monks, Eastern monastics, Celtic monasticism, later Cistercians, Carthusians, Franciscans, Dominicans, and many other movements sought prayer, poverty, discipline, learning, and reform. Monasteries preserved texts, cultivated liturgy, educated clergy, received pilgrims, managed land, and produced theology and mysticism.

Medieval Christianity created universities, scholastic theology, canon law, pilgrimage networks, crusades, saints' cults, parish systems, cathedrals, vernacular devotion, and mystical literature. It also produced anti-Judaism, inquisitions, coercion, holy war, and clerical corruption. The beauty and violence of Christendom belong to the same historical world.

VI. Eastern, Oriental, Western

Christianity is not simply Roman Catholicism plus Protestantism. The Church of the East, Oriental Orthodox churches, Eastern Orthodoxy, Roman Catholicism, and later Protestant churches preserve different histories of language, empire, Christology, liturgy, and authority. Syriac, Coptic, Armenian, Georgian, Greek, Latin, Slavonic, Arabic, Ethiopic, and many other Christian languages matter.

The split between Eastern and Western Christianity developed over centuries through language, authority, liturgy, politics, and theology. The 1054 date is symbolic rather than a single clean break. Eastern Orthodoxy emphasizes conciliarity, liturgy, icons, theosis, and continuity with the fathers. Roman Catholicism developed papal primacy, scholastic theology, canon law, and global institutional reach. Oriental Orthodox traditions preserve non-Chalcedonian Christologies and ancient liturgical worlds often misunderstood by outsiders.

Global Christianity today cannot be understood if these older eastern and African Christianities are treated as marginal. Ethiopian, Coptic, Syriac, Armenian, Indian, and Orthodox traditions are not footnotes to Western church history.

VII. Reformation, Catholic Reform, and Modern Denominations

The Protestant Reformation shattered Western Christendom. Luther, Zwingli, Calvin, the Radical Reformation, Anglican reformers, and many local movements challenged indulgences, papal authority, sacramental theology, clerical mediation, and the relation between scripture and tradition. The slogans of grace, faith, scripture, and Christ alone condensed complex theological and institutional struggles.

Catholic reform responded through the Council of Trent, new religious orders, missionary expansion, seminary formation, discipline, art, mysticism, and renewed sacramental life. The result was not simply Catholic versus Protestant. It was a plural Western Christianity of Lutherans, Reformed, Anglicans, Anabaptists, Baptists, Methodists, Pentecostals, restoration movements, independent churches, and many others.

Modern denominations are not merely administrative divisions. They carry different answers to authority, grace, baptism, Eucharist, scripture, ministry, holiness, spiritual gifts, social reform, and church discipline. Pentecostalism and charismatic Christianity, especially, have reshaped global Christianity through healing, tongues, deliverance, music, lay participation, and rapid growth in the Global South.

VIII. Mission, Colonialism, Liberation, and Global Christianity

Christian mission spread scripture, liturgy, schools, medicine, printing, translation, and new communities. It was also entangled with empire, conquest, slavery, cultural destruction, and racial hierarchy. Christianity justified colonization and inspired resistance to it. It underwrote slavery and abolition. It produced both mission schools and Indigenous revivals, both imperial theology and liberation theology.

African, Asian, Latin American, Indigenous, and diasporic Christianities are now central, not peripheral. The demographic center of Christianity has shifted southward and eastward. Latin American Catholicism and Pentecostalism, African Independent Churches, Korean Protestantism, Chinese Christianity, Indian Christianity, Filipino Catholicism, Ethiopian Orthodoxy, and migrant churches all belong at the center of the modern story.

Christianity is therefore not owned by Europe, though European history shaped it deeply. The future of Christianity is multilingual, postcolonial, charismatic, liturgical, migrant, and contested.

IX. Reading the Christian Shelf

The Christian shelf should be read by genre and tradition. Scripture, creed, hagiography, sermon, mystical treatise, monastic rule, scholastic argument, liturgy, hymn, history, polemic, and modern manifesto each do different work. A patristic homily is not a Reformation tract. A medieval saint's life is not a modern biography. A mystical vision is not a systematic theology. A colonial missionary text may preserve language and violence at once.

The reader should ask: Which Jesus is being proclaimed? Which church is assumed? What authority governs the text: scripture, bishop, council, Spirit, tradition, conscience, reason, or experience? What practice does the text form: prayer, obedience, reform, contemplation, mission, protest, sacrament, or community?

Christianity's archive is enormous because its central claim is enormous: that the eternal Word entered history, that death was answered by resurrection, and that human communities must live as if that is true. Everything else is argument over what that means.

X. Source Problems and Historical Method

Christian sources must be read with attention to genre, date, and community. A canonical gospel, a Pauline letter, a martyr act, a conciliar creed, a monastic rule, a medieval miracle collection, a Protestant confession, and a Pentecostal testimony do not make truth claims in the same way. Some are liturgical; some are polemical; some are pastoral; some are legal; some are visionary; some are historical narratives shaped by theological conviction.

The New Testament itself is both scripture and a collection of first-century and early second-century texts. Historical study asks about authorship, community, redaction, oral tradition, manuscript transmission, and social setting. Theological reading asks how the church receives the text as Word of God. These approaches can conflict, but they need not be collapsed. A public religious library should let readers see both the faith-use and the historical-use of Christian texts.

Translation is also a source problem. Greek terms such as ekklesia, pistis, dikaiosyne, logos, sarx, pneuma, agape, and euangelion carry meanings that English words only approximate. Latin terms such as sacramentum, gratia, caritas, and ecclesia shaped Western theology. Syriac, Coptic, Armenian, Slavonic, Ge'ez, and vernacular Christian languages carry different theological textures. Christianity is a translation religion, and every translation becomes interpretation.

XI. Gender, Body, and the Ordinary Christian Life

Christianity has repeatedly made the body a theological site. Baptism washes the body; Eucharist feeds it; fasting disciplines appetite; celibacy, marriage, childbirth, sickness, disability, martyrdom, burial, and relics all become religiously charged. Christian theology can affirm the body through incarnation and resurrection while also fearing desire, corruption, and mortality. That tension shapes monasticism, sexual ethics, gender roles, medicine, and devotion.

Women have been central to Christianity from the beginning: Mary the mother of Jesus, Mary Magdalene and other women witnesses, female patrons of Pauline communities, martyrs, desert mothers, abbesses, mystics, missionaries, reformers, Pentecostal leaders, theologians, and lay organizers. At the same time, Christian institutions often restricted women's authority through clerical structures, household codes, and theological arguments about gender. A serious account must hold both realities.

Everyday Christianity is often less dramatic than councils and reformations. It is teaching children to pray, burying the dead, singing hymns, lighting candles, reading scripture, feeding neighbors, confessing sins, blessing houses, keeping feast days, arguing in vestries, building schools, visiting prisoners, and gathering at tables. The scale of Christianity is civilizational, but its continuity is often domestic.

XII. Authority, Conscience, and Modern Crisis

Christianity's internal conflicts often turn on authority. Who may interpret scripture? Who may ordain? What binds the church: Bible, tradition, bishop, pope, council, confession, Spirit, reason, conscience, or community? Roman Catholicism, Eastern Orthodoxy, Protestantism, Pentecostalism, and independent churches answer differently. These answers shape everything from worship to politics.

Modern Christianity has faced historical criticism, evolutionary science, secular states, capitalism, socialism, feminism, racial justice, sexual ethics, ecological crisis, and religious pluralism. Some Christians respond by defending tradition; some revise doctrine; some retrieve older resources; some form new movements; some leave institutions while keeping devotion. Modernity did not simply weaken Christianity. It forced Christianity to clarify what kind of truth it claims.

The tradition's public record is morally mixed. Christians have blessed slavery and fought it, justified empire and resisted it, excluded women and elevated women saints, persecuted minorities and defended human dignity. This is not a reason to stop reading Christianity. It is a reason to read it truthfully. The archive contains both gospel and failure.

The best Christian reading practice is therefore double vision. One eye watches doctrine: Trinity, incarnation, creation, sin, grace, church, sacrament, resurrection, kingdom. The other watches social body: who has power, who is excluded, who speaks, who suffers, who serves, who translates, who preserves the text. Christianity is never only an idea. It becomes visible in institutions and persons.

For this library, that means Christian texts should be allowed to disagree. Augustine, Bede, Julian, Luther, a Syriac hymn, an Ethiopian homily, a Quaker testimony, and a Pentecostal sermon do not collapse into one voice. They form a history of people trying to answer the same central claim under different conditions: Christ is risen, and the world must be read in that light.

That is why Christianity needs an encyclopedia shelf rather than a single summary. Its sources are not redundant; they are witnesses to the way one confession becomes many lives, institutions, wounds, and hopes across time, language, empire, family, suffering, reform, and prayer.

The shelf should therefore remain generous. A small creed can name the center, but only a wide archive can show how that center was preached, sung, painted, weaponized, healed, doubted, defended, translated, and lived.

Sources Consulted and Further Reading