Heresies & Orthodoxy

Claimed: Salvation comes through secret spiritual knowledge (gnosis), for the material world was made not by the supreme God but by an inferior demiurge, and Christ only appeared to be truly human.

The church answered Gnosticism above all through Irenaeus of Lyons, whose Against Heresies (c. 180) argued that the one God is both Creator and Redeemer, that the apostolic faith is public — preserved in the rule of faith, the Scriptures of both Testaments, and the open succession of bishops — not a private secret, and that Christ truly took flesh to heal what he assumed. Tertullian, Hippolytus, and Clement of Alexandria continued the refutation. The struggle pushed the church to define its canon and creedal rule of faith.

No single council; refuted by the 2nd-century Fathers (Irenaeus, Tertullian) and excluded by the rule of faith

Claimed: The God of the Old Testament is a harsh creator distinct from and inferior to the loving Father revealed by Jesus, so the Old Testament must be rejected and the Christian Scriptures reduced to an edited Luke and ten Pauline letters.

Marcion was excommunicated by the church at Rome in 144. Tertullian's five books Against Marcion mounted the classic reply: the Creator and the Father of Jesus Christ are one God, the Old Testament prophesies Christ, and justice and mercy belong to the same divine character. Irenaeus likewise insisted on the unity of the two Testaments. Marcion's truncated canon spurred the church to affirm the Old Testament and to recognize its own fourfold Gospel and wider apostolic canon.

Excommunication of Marcion at Rome (144); no ecumenical council

Claimed: Montanus and the prophetesses Priscilla and Maximilla spoke as direct mouthpieces of the Holy Spirit, delivering a binding 'New Prophecy' of ecstatic revelation and severe discipline that went beyond the apostolic faith.

Synods of bishops in Asia Minor in the later 2nd century — the earliest recorded church synods — examined the New Prophecy and excluded its adherents from communion, a judgment recounted by Eusebius. The church did not deny the Spirit's ongoing work but rejected the claim that new ecstatic revelation could supplement or supersede the faith delivered through the apostles, anchoring authority in Scripture and the episcopate. Montanism's most famous convert, Tertullian, joined the movement in later life.

Synods in Asia Minor (late 2nd century); later condemned by various councils

Claimed: Father, Son, and Holy Spirit are not distinct persons but successive modes or roles in which the one God appears, so that the Father himself, in another guise, suffered on the cross.

Tertullian's Against Praxeas and the writings of Hippolytus refuted modalism by articulating one divine substance in three real, distinct persons — coining much of the church's Trinitarian vocabulary. Sabellius himself was excommunicated at Rome under Callistus (c. 220). The church saw that modalism destroys the reality of the Son's relationship to the Father — his prayer, obedience, and sending — which Scripture presents as between distinct persons. The Niceno-Constantinopolitan Creed's confession of three distinct persons excludes it definitively.

Excommunication of Sabellius at Rome (c. 220); excluded by the creed of First Council of Constantinople (381)

Claimed: The Son of God is not eternal but the first and greatest of creatures, made by the Father out of nothing, so that 'there was when he was not.'

The First Council of Nicaea (325) condemned Arius and confessed the Son as 'begotten, not made, of one substance (homoousios) with the Father.' Athanasius of Alexandria spent his career, through five exiles, defending Nicaea: only one who is truly God can unite humanity to God and save it. The Cappadocian Fathers — Basil, Gregory of Nazianzus, and Gregory of Nyssa — completed the theological victory, and the First Council of Constantinople (381) reaffirmed the Nicene faith against Arianism's later forms.

First Council of Nicaea (325); reaffirmed at First Council of Constantinople (381)

Claimed: In Christ the divine Logos took the place of a human rational soul, so that Christ had a true human body but not a complete human mind.

Gregory of Nazianzus supplied the decisive answer: 'What has not been assumed has not been healed.' If Christ lacked a human mind, then the human mind — the very seat of sin — remains unredeemed. The church insisted that the Savior took complete human nature, body and rational soul, while remaining one person. Apollinarianism was condemned by synods at Rome under Damasus in the 370s and definitively by the First Council of Constantinople (381).

First Council of Constantinople (381)

Claimed: The divine Son and the man Jesus are so distinct that Mary should be called Christotokos rather than Theotokos, language heard as dividing Christ into two persons joined only by moral union.

Cyril of Alexandria argued that the eternal Word is the single subject of everything Christ does and suffers: the one born of Mary is God the Son, so she is rightly called Theotokos, 'God-bearer.' To divide Christ into two persons is to make the cross the death of a mere man and empty the Eucharist of its life-giving power. The Council of Ephesus (431), endorsing Cyril's letters, deposed Nestorius and upheld the unity of Christ's person.

Council of Ephesus (431)

Claimed: After the incarnation Christ has only one nature, his humanity being absorbed into his divinity like a drop of honey in the sea, so that he is not consubstantial with us.

Pope Leo I's Tome to Flavian insisted that in Christ each nature remains complete and active — 'each form does what is proper to it' — in the one person. The Council of Chalcedon (451) deposed Eutyches' protector Dioscorus and defined that Christ is perfect in Godhead and perfect in manhood, one person in two natures 'without confusion, without change, without division, without separation.' A humanity dissolved into deity could neither represent us nor redeem us; salvation requires that Christ be truly one of us.

Council of Chalcedon (451)

Claimed: Human beings are born without inherited sin and can, by their natural free will and effort, obey God's commands and attain salvation without the inward aid of divine grace.

Augustine of Hippo led the church's response, arguing from Scripture and from the church's practice of infant baptism that humanity inherits a fallen condition from Adam and that grace is not merely instruction or example but God's inward transformation of the will — 'give what you command, and command what you will.' The Council of Carthage (418) condemned Pelagian teaching in a series of canons, the Council of Ephesus (431) condemned Pelagius' ally Caelestius, and the Second Council of Orange (529) later affirmed the necessity of prevenient grace.

Council of Carthage (418); Council of Ephesus (431)

Claimed: Although Christ exists in two natures, he has only one will and one energy, the divine.

Maximus the Confessor argued that will belongs to nature, not person: a human nature without a human will is not a real humanity, and Christ's prayer in Gethsemane — 'not my will, but thine, be done' — shows a genuine human will freely conformed to the divine. Maximus was mutilated and exiled for this confession, and Pope Martin I died in exile for it. Vindicating them, the Third Council of Constantinople (680–681) defined that Christ has two natural wills and two natural energies in unbroken harmony.

Third Council of Constantinople (680-681)

Claimed: Making and venerating images of Christ and the saints is idolatry forbidden by the second commandment, and icons of Christ either divide his natures or circumscribe his divinity.

John of Damascus and later Theodore the Studite answered that the incarnation changed everything: the invisible God has been truly seen in the flesh, so Christ can be depicted, and to deny this verges on denying the incarnation itself. Honor given to an image passes to its prototype, and veneration (proskynesis) of icons differs in kind from the worship (latreia) due to God alone. The Second Council of Nicaea (787) restored the icons on these grounds; after a second iconoclast period, the icons were finally restored in 843, the 'Triumph of Orthodoxy.'

Second Council of Nicaea (787)