Theological and Historical Terms & Definitions

Heresy: A belief or teaching contrary to official Church doctrine.
Orthodoxy: Correct or accepted belief, especially in theology.
Apologetics: Defense of Christian doctrine against critics and heretics.
Christology: Study of the person and nature of Jesus Christ.
Hypostatic Union: The union of divine and human natures in the one person of Jesus Christ.
Dualism: Belief in two opposing forces (e.g., good vs. evil); rejected by the Church.
Asceticism: Practice of self-discipline and renunciation for spiritual purposes.

Canon: Official list of texts recognized as Scripture by the Church.
Muratorian Fragment: Oldest known list of New Testament books (late 2nd century).
Papias of Hierapolis: Early Church writer who emphasized oral tradition and eyewitness testimony.
Tradition: Transmission of teachings from apostles through bishops and Church practices.
Apostolic Succession: The line of bishops traced back to the apostles, ensuring continuity of faith.
Monarchical Episcopate: Church leadership structure with a single bishop at the head of each community.
Ignatius of Antioch: Early bishop who emphasized unity under the bishop as a representative of God.

Nestorius: Patriarch of Constantinople; claimed Christ had two persons (divine & human).
Cyril of Alexandria: Opposed Nestorius; emphasized unity of Christ’s person (one nature).
Theotokos: "God-bearer"; title for Mary affirmed at Council of Ephesus (431).
Monophysitism: Belief that Christ has one nature (divine); rejected at Chalcedon.
Eutyches: Promoted Monophysitism; his views led to Council of Chalcedon.
Latrocinium: "Robber Council" (Ephesus 449); rejected Leo’s two-natures theology.
Tomus ad Flavianum: Letter from Pope Leo affirming Christ’s two natures.
Council of Ephesus (431): Condemned Nestorius; affirmed Mary as Theotokos.
Council of Chalcedon (451): Defined Christ as one person in two natures (divine & human).

Arianism: Belief that Jesus was a created being and not equal to God the Father.
Arius: Alexandrian priest who promoted Arianism.
Athanasius: Opponent of Arius; defended Christ’s full divinity.
Council of Nicaea (325): Condemned Arianism; affirmed Christ is "of one substance" with the Father.
Nicene Creed: Statement of Christian belief affirming the full divinity of the Son.
Homoousios: Greek for "of one substance"; key term used to affirm Christ’s divinity.

Papal Primacy: Claim that the Pope (Bishop of Rome) holds supreme authority in the Church.
Church of Constantinople: Powerful Eastern Church that often clashed with Rome.
Schism: Division within the Church over doctrine or authority.
Papacy: The office and role of the Pope.

Barbarian Kingdoms: Germanic tribes like the Visigoths and Franks that adopted forms of Christianity.
Christianization: Process of converting individuals or tribes to Christianity.
Emperor Justinian I: Byzantine emperor who enforced orthodoxy and expanded the empire.
Three Chapters Controversy: Dispute over writings seen as sympathetic to Nestorianism.
Pope Vigilius: Involved in the Three Chapters dispute; caused regional schisms.
Ravenna: Church center closely tied to Byzantine authority.

St. Benedict of Nursia: Founder of Western monasticism; wrote the Rule of Benedict.
Rule of Benedict: Guide for balanced monastic life focused on prayer, work, and humility.

Spread through rural Europe; known for scholarship and missionary work.
St. Columbanus: Irish monk who founded monasteries in Europe (e.g., Bobbio).