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What Is the Orthodox Church?

An introduction to Eastern Orthodox Christianity: its history, beliefs, worship, and what makes it distinct from other Christian traditions.

The Ancient Christian Faith

The Orthodox Church traces its origins directly to Jesus Christ and the apostles. Orthodox Christians believe they have maintained the faith "once delivered to the saints" (Jude 1:3) in an unbroken line from the Day of Pentecost to the present. With approximately 300 million members worldwide, Orthodoxy is the second-largest Christian communion after the Roman Catholic Church.

What Does 'Orthodox' Mean?

The word 'Orthodox' comes from the Greek words orthos (right, true) and doxa (glory, worship, or belief). It means both 'right belief' and 'right worship'—a fitting name for a tradition that sees theology and liturgy as inseparable. The Church is also called 'Eastern' because it developed primarily in the Greek-speaking eastern half of the Roman Empire.

Apostolic Succession and Holy Tradition

Orthodox Christians believe that the bishops of the Church stand in an unbroken line of succession from the apostles, who received their authority directly from Christ. This apostolic succession ensures the faithful transmission of Holy Tradition—the living faith of the Church expressed through Scripture, the Ecumenical Councils, the writings of the Church Fathers, the liturgy, iconography, and the lives of the saints.

The Holy Trinity

At the heart of Orthodox faith is belief in the Holy Trinity: one God in three Persons—Father, Son, and Holy Spirit. The Nicene Creed, confessed at every Divine Liturgy, summarizes this faith. Orthodox Christians believe that Jesus Christ is fully God and fully human, and that through His incarnation, death, and resurrection, humanity is offered salvation and union with God.

Worship and the Divine Liturgy

Orthodox worship is liturgical, centered on the Divine Liturgy—the celebration of the Eucharist. The liturgy draws the faithful into the heavenly worship described in the Book of Revelation, using incense, icons, chanting, and ancient prayers. For Orthodox Christians, worship is not merely an activity but participation in the eternal worship of the angels and saints.

Icons and Sacred Images

Orthodox churches are filled with icons—sacred images of Christ, the Theotokos (Mary, Mother of God), angels, and saints. Icons are not idols; they are windows into heaven, aids to prayer, and affirmations that God truly became human in Jesus Christ. The veneration of icons was defended by the Seventh Ecumenical Council in 787.

Theosis: The Goal of the Christian Life

The Orthodox understanding of salvation centers on theosis (deification)—becoming by grace what God is by nature. St. Athanasius wrote, "God became man so that man might become god." This does not mean becoming equal to God in essence, but rather sharing in the divine life, being transformed by the Holy Spirit to reflect God's love and holiness.

The Church's Structure

The Orthodox Church is organized as a communion of self-governing (autocephalous) churches, including the Ecumenical Patriarchate of Constantinople, the Patriarchates of Alexandria, Antioch, Jerusalem, Moscow, and others. Each maintains the same faith and sacraments while being administratively independent. The Ecumenical Patriarch holds a primacy of honor among equals but has no jurisdiction over other churches.

Coming to Orthodoxy

Many people discover the Orthodox Church through its ancient liturgy, its unchanged doctrine, or its rich spiritual tradition of prayer and asceticism. The Orthodox Church welcomes all who seek Christ. Those interested in learning more are encouraged to attend a Divine Liturgy, speak with an Orthodox priest, and read the Church's teachings for themselves.

Frequently Asked Questions

How is the Orthodox Church different from the Catholic Church?

The Orthodox Church and Roman Catholic Church separated in 1054. Key differences include the Orthodox rejection of papal supremacy and infallibility, the Filioque clause in the Creed, and certain theological emphases. However, both churches share much in common, including apostolic succession, seven sacraments, and veneration of Mary and the saints.

Can anyone attend an Orthodox church service?

Yes! All are welcome to attend the Divine Liturgy and other services. However, only Orthodox Christians in good standing may receive Holy Communion. Visitors are encouraged to arrive a few minutes early and simply observe the beauty of the worship.

Sources

  • Timothy Ware, The Orthodox Church (Penguin, revised 1993), chapters 1–3
  • Nicene-Constantinopolitan Creed (381)
  • St. Athanasius, On the Incarnation
  • Seventh Ecumenical Council (Nicaea II, 787)

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