Ecumenical Councils, Sacraments, and Orthodox Theology

A comprehensive set of vocabulary flashcards covering ecumenical councils, key heresies, sacramental theology, Christology, soteriology, and comparative points between Orthodox, Protestant, and Catholic teachings.

Ecumenical Council

A universal gathering of the church’s bishops to settle doctrinal or pastoral issues

Jerusalem Council

The first church council (Acts 15) that decided how Gentiles could enter the faith

Council of Nicea (325 AD)

318 bishops condemned Arius and composed the first part of the Creed

Arius

Alexandrian priest who taught that the Son was a created being, inferior to the Father

Heresy of Arius

Denial of the Trinity; claim that “there was when the Son was not”

Homoousios

Greek for “of one essence”; affirms the Son is equal with the Father

St Athanasius

Deacon at Nicea who became chief defender of Trinitarian orthodoxy

Council of Constantinople (381 AD)

150 bishops expanded the Creed and condemned Macedonius and Apollinaris

Macedonius

Bishop of Constantinople who denied the divinity of the Holy Spirit

Macedonianism

Heresy claiming the Holy Spirit is a created, inferior being

Apollinaris

Syrian bishop who said Christ’s human spirit was replaced by the Divine Logos

Apollinarianism

Heresy denying Christ’s full humanity (no human rational spirit)

Council of Ephesus (431 AD)

200 bishops excommunicated Nestorius and wrote the Creed’s introduction

Nestorius

Bishop of Constantinople who separated Christ’s divinity and humanity

Nestorianism

Doctrine of two disconnected persons in Christ; rejected title Theotokos

St Cyril of Alexandria

Patriarch who defended “one nature of the Incarnate Logos” and issued 12 Anathemas

Theotokos

Greek for “God-bearer”; Orthodox title for St Mary

Christotokos

Title proposed by Nestorius meaning “Christ-bearer,” excluding divine maternity

12 Anathemas

Cyril’s statements condemning errors about Christ’s single united nature

One Nature of the Incarnate Logos

Cyril’s formula (mia-physis) expressing the unity of Christ’s divinity and humanity

Sacrament (Mystery)

Holy ordinance instituted by Christ granting invisible grace through visible signs

Seven Sacraments

Baptism, Chrismation, Eucharist, Confession, Unction, Matrimony, Holy Orders

Baptism

Immersion in water in the Trinitarian name that grants rebirth and church membership

Immersion

Complete dipping in water, the biblical mode signified by the Greek baptizo

Chrismation

Anointing with Holy Myron that bestows the Holy Spirit and confirms new life

Myron Oil

Consecrated oil used to anoint 36 crosses during Chrismation

Repentance and Confession

Sacrament where sins are confessed to a priest and absolved by Christ’s authority

Absolution

Priest’s declaration of God’s forgiveness, accompanied by laying on of hands

Eucharist

Receiving Christ’s Body and Blood under bread and wine; “crown of sacraments”

Offering of Melchizedek

Old-Testament bread-and-wine sacrifice foreshadowing the Eucharist

Passover Lamb

Blood that saved Israel; symbol of Christ’s sacrificial Eucharist

Manna

Heavenly bread in the desert prefiguring the Eucharist

Holy Matrimony

Sacrament uniting a man and woman as one flesh, icon of Christ and the Church

Wedding at Cana

Christ’s first miracle blessing marriage and prefiguring sacramental transformation

Unction of the Sick

Anointing with oil and prayer for healing and forgiveness

Priesthood (Holy Orders)

Sacrament instituting bishops, priests, and deacons with authority to bind and loose

Trinity

One God in three co-essential Persons: Father, Son, and Holy Spirit

Hypostasis

Distinct person within the one divine essence

Incarnation

The Word becoming flesh, uniting divine and human natures in Christ

Divinity of Christ

Truth that Jesus is fully God, shown by miracles, teachings, and resurrection

Atonement

Christ’s sacrificial death satisfying divine justice and granting forgiveness

Original Sin

State of corruption and death inherited from Adam’s fall

Adoption

Becoming children of God through union with Christ, the Bridegroom

Salvation (Orthodox view)

Lifelong process received by faith, sacraments, and good works

Filioque

Latin addition “and the Son” to the Creed about the Spirit’s procession; rejected by Orthodoxy

Immaculate Conception

Catholic dogma of Mary’s sinless conception; denied by Orthodox teaching

Purgatory

Catholic doctrine of post-mortem purification, viewed as contrary to complete atonement

Primacy of Peter

Catholic claim of Peter’s supremacy; Orthodox see Christ’s Church built on Peter’s faith

Papal Infallibility

Catholic belief that the pope cannot err in ex cathedra teachings; not accepted by Orthodoxy

Eutychianism

Heresy that Christ’s humanity dissolved into divinity, forming a single confused nature

Without Separation or Division

Orthodox phrase affirming inseparable union of Christ’s two natures

Without Mingling or Confusion

Assertion that divinity and humanity remain distinct in Christ

Without Alteration

Teaching that neither nature changed when Word became flesh

Divine Dilemma

St Athanasius’ description of God’s justice vs. mercy after human sin

Ark of Noah (Baptism symbol)

OT figure of salvation through water carrying the faithful to safety

Circumcision (Baptism symbol)

Cutting off flesh on eighth day, prefiguring death to sin in baptism

Red Sea Crossing

Israel’s passage through water to freedom, typology of baptismal salvation

Visible Signs

Material actions (water, oil, bread) through which sacramental grace is conveyed

Invisible Grace

Spiritual gift received inwardly in each sacrament

Iron-and-Fire Analogy

Cyril’s image of united yet distinct divinity and humanity in Christ

Dove

Visible symbol of the Holy Spirit at Christ’s baptism

Tongues of Fire

Manifestation of the Holy Spirit on Pentecost

Laying on of Hands

Apostolic gesture signifying impartation of the Spirit or consecration

Intercession (Orthodox)

Saints’ prayers for the faithful, distinguished from Christ’s unique redemptive mediation

Septuagint

Greek OT canon accepted by Orthodox, including Deuterocanonical books

Apostolic Succession

Unbroken transmission of faith and ministry from the apostles through the bishops

Doctrinal Development (Catholic view)

Idea that church’s understanding can evolve beyond early Fathers; contrasted with Orthodox preservation

Unlimited (attribute for Redeemer)

Quality required for atonement: only an infinite person can offer infinite satisfaction

Sinless (attribute for Redeemer)

Freedom from any personal sin, necessary for one who redeems others

Mortal (attribute for Redeemer)

Ability to die, so the Savior can pay sin’s wage on humanity’s behalf