In the centuries following the conversion of the ancient world, precise definition was given to Christian teaching on basic truths of faith — on the Blessed Trinity, on the mysteries of Christ and on the question of grace.

1. The Ecumenical Councils

The Christian-Roman period was extremely important from the point of view of doctrine. Now that the Church was free, the historic moment came for it to give precise formulation to orthodox teaching on basic questions of Christian faith — the Blessed Trinity, the mystery of Christ, and the question of grace. The definition of catholic dogma occurred in the context of heated theological battles against heresies which led to schisms in the Church, some of which are still with us.

The ecumenical councils played an important role in this task of defining catholic dogma. Eight ecumenical councils, between the fourth and ninth centuries, constituted the first cycle of councils in Church history. The First Council of Nicaea (325), which defined the consubstantiality of the Son with the Father; The First Council of Constantinople defined the divinity of the Holy Spirit(381). The Council of Ephesus (431) proclaimed the Divine Maternity of Mary; that ofChalcedon (451) defined the doctrine of the two natures in the one person of Christ. TheSecond Council of Constantinople (553) condemned Nestorianism, and the Third Council of Constantinople (680-681) formulated the doctrine of the Two Wills of Christ.

In the two early councils, the theological doctrine of the Blessed Trinity was defined and the four next councils formulated the fundamental Christological truths. Two other ecumenical councils were also held in the East: The Second Council of Nicaea (787), which formulated theorthodox doctrine on iconoclasm, and the Fourth Council of Constantinople (869-870), which put an end to the Photian Schism which however, persisted in the Greek Church. Upon closer look at their historical and doctrinal context, the first six ecumenical councils actually defined the Trinitarian and Christological doctrines of the Catholic faith.

2. Formation of the Dogma of the Blessed Trinity

The fourth century saw the formulation of dogma concerning the Trinity, with catholic orthodoxy having to confront Arianism. Arianism can be traced back to certain early doctrines which overemphasized the oneness of God, to the extent of obliterating the distinction of persons in the Blessed Trinity (Sabellianism) or of ‘subordinating’ the Son to the Father, making him inferior to the Father (subordinationism). A radical subordinationism inspired the teaching ofArius, an Alexandrian priest (c. 250-336), who not only held that the Son was inferior to the Father, but went as far as denying that Jesus was God. The absolute oneness of God which Arius proclaimed led him to see the Word as simply the noblest of all created beings, not as the natural Son of God: Christ was God’s adopted son and therefore only in an improper sense could he be called God.

Arian teaching was clearly influenced by Greek philosophy with its notion of the Supreme God — Summus Deus — and a concept of the Word very akin to Plato’s demiurge, a being intermediate between God and the universe who was the shaper of creation. This connexion between Arianism and Greek philosophy accounts for its rapid spread and for its being welcomed by rationalist intellectuals involved with hellenism. Arianism had very serious consequences on Christian teaching, affecting as it did the dogma of the redemption: for if the incarnate Word, Jesus Christ, were not God, then redemption would be ineffective. The churchof Alexandria realised the seriousness of the problem and, after attempting to dissuade Arius of his error, it proceeded to condemn him at a synod of the bishops of Egypt (318). But Arianism was already a world-wide problem and it led to the convoking of the first ecumenical council in history.

3. The First Council of Nicaea (325) and the formulation of the Nicene Creed

The first council of Nicaea (325) was a clear victory for the defenders of orthodoxy, two of the most outstanding of whom were bishops — Ossius of Cordova (Spain) and a deacon (and later bishop) of Alexandria, Athanasius. The council defined the divinity of the Word, using an unambiguous term to describe his relationship with the Father — homoousios, ‘consubstantial.’ The Nicene symbol or creed proclaimed that the Son, Jesus Christ, ‘God from God, Light from Light, true God from true God, begotten, not made,’ is ‘consubstantial’ with the Father.

Orthodoxy’s victory at Nicaea was followed, however, by a post-council period of a radically opposed viewpoint, which constituted one of the most surprising episodes in Christian history. The pro-Arian party, led by Eusebius, bishop of Nicomedia, managed to exert a decisive influence at the imperial court and in the last years of Constantine’s reign and during the reigns of his successors it looked as if Arianism was going to prevail. The most outstanding of the Nicene bishops were exiled and, as St Jerome graphically put it, ‘the whole world groaned and discovered to its surprise that it had become Arian.’

4. The First Council of Constantinople

From the middle of the fourth century on, Arianism was divided into three factions: the radical Anomoeans, who laid emphasis on the dissimilarity of the Son with respect to the Father; the Homoeans, who regarded the Son as homios — that is, ‘like to’ — the Father; and what are called semi-Arians — those nearest orthodoxy — for whom the Son was’substantially like’ the Father.

The theological work of what are called the Cappadocian Fathers developed the teaching of Nicaea and attracted many supporters of the more moderate tendencies in Arianism, with the result that in a very short time Arianism disappeared from the horizon of the universal Church, surviving only as the form of Christianity professed by most of the Germanic nations who had invaded the empire. The theology of the Trinity was completed at the first council of Constantinoplewith the definition of the divinity of the Holy Spirit (in reaction to another heresy —Macedonianism).

Thus, by the end of the fourth century, catholic doctrine on the Blessed Trinity had been fixed in the form of Niceno-Constantinopolitan creed. However, there was one aspect of Trinitarian theology not expressly dealt with in the Creed — the relationships between the Holy Spirit and the Son. This would later give rise to the famous Filioque problem, which was to become an apple of discord between the Christian east and the Christian west.

5. The Humanity and Divinity of Jesus Christ

Once the doctrine of the Blessed Trinity had been defined, theology had to deal with the mystery of Christ, not in relation to the other divine persons, but in regard to the nature of Christ himself. The basic problem was this: Christ is perfect God and perfect man; but how do divinity and humanity combine in man? On this question, the two great theological schools of the east took opposite sides.

The Alexandrian school laid emphasis on the perfect divinity of Jesus Christ: his divine nature so penetrates his human nature — like fire heating an iron — that an internal unity results, a kind of ‘mixture’ of natures. The Antiochene school stressed, instead, the perfect humanity of Christ: the unity of the two natures in him is only external or moral in such a way that rather than speak of ‘incarnation’ it would be more correct to speak of the ‘indwelling’ of the Word, who’dwells’ in the man Jesus as inside a garment or a tent.

This Christological problem came out in the open when Nestorius, the bishop of Constantinople, who belonged to the Antiochene school, preached in public against the divine maternity of Mary, refusing to give her the title of Theotokos, ‘God-bearer,’ Mother of God; she was, he said, only theChristotokos, ‘Mother of Christ.’ This led to popular demonstrations and the denunciation of Nestorius’ doctrine to Rome by St Cyril, the patriarch of Alexandria. Pope Celestine I asked Nestorius to retract, which he refused to do.

The council of Ephesus (431), now summoned by the emperor, Theodosius II, had a very rough passage due to rivalry between Alexandrine and Antiochene bishops; but eventually agreement was reached and a profession of faith was composed for which was formulated the doctrine of the ‘hypostatic union’ of the two natures in Christ and Mary was acknowledged as Mother of God. Nestorius was deposed and sent into exile; however, groups of his followers continued to exist in the near east forming a Nestorian church which carried out a great deal of missionary work, over a number of centuries, in countries of Asia.

6. The Council of Chalcedon

By the first half of the fifth century the patriarchate of Alexandria had grown in power and many of its bishops took an active part in the internal affairs of the church of Constantinople itself. It also happened that after the death of St Cyril extremist tendencies gained the upper hand in Alexandria. The Alexandrian theologians were unhappy about the Ephesus teaching on the two natures in the one person of Christ, due to their understanding two natures as being equivalent to two persons: they claimed that there was only one nature inChrist, because in the incarnation the human nature had been absorbed in the divine.

When this doctrine — monophysitism — was preached in Constantinople by the archimandriteEutyches, Flavian the patriarch deprived Eutyches of his office. The patriarch of Alexandria,Dioscorus, then intervened, with the support of Emperor Theodosius II. An unruly council was held at Ephesus (449) under the presidency of Dioscorus; the patriarch of Constantinoplewas deposed and exiled; a dogmatic letter sent to Flavian by the pope, by the hand of two papal legates, was prevented from being read, and the doctrine of the two natures in Christ was condemned. The pope, Leo the Great, gave this council a name which was passed into history — the ‘latrocinium of Ephesus.’

As soon as Emperors Pulcheriaand Marcian succeededTheodosius II, Pope Leo asked that a new ecumenical council meet: this, was the council of Chalcedon (451). This council adhered unanimously to the Christological teaching contained in Leo the Great’s letter to Flavian: ‘Peter has spoken through the mouth of Leo’, the fathers proclaimed. Chalcedon’s profession of faith recognized that there were two natures in Christ’without their being any confusion or division or separation between them.’

But monophysitism, far from disappearing, put down deep roots in various parts of the east, especially in Egypt, where it was used as a secessionist banner against the authority of the empire. The condemnation of monophysitism was taken as an attack on the traditions of Athanasiusand Cyril. A monophysite patriarchate grew up in Alexandria (supported by the monks and the indigenous Coptic population) in opposition to the melchite or imperial patriarchate.

This historical context explains why the succeeding emperors strove to find compromise formulas which, without contradicting the symbol of Chalcedon, would be more acceptable to the monophysites and would thereby assure the loyalty of the population of these areas to the empire. Examples of this were the Henotikon — an edict of Emperor Zeno (482) — and the famous question of the ‘Three Chapters,’ proposed unsuccessfully by Justinian, which produced unfavourable reactions in the west.

The most serious effort in this direction was that backed by Emperor Heraclius, an energetic defender of the Christian east against the Persians and Arabs. Sergius, patriarch of Constantinople, thought that, without denying Chalcedonian teaching on the two natures, it could be held that, by virtue of the hypostatic union, there was in Christ only one divine-human activity(monoenergism) and that Christ had only one will (monothelitism). Heraclius sanctioned this doctrine by his dogmatic decree Ecthesis (638). But Ecthesis solved nothing, neither in the field of religion nor in that of politics. The monophysites rejected it, and in a very short time Palestine, Syria and Egypt were in the hands of the Arabs.

The Christological debate came to an end when the third council of Constantinople (the sixth ecumenical council), on the basis of letters sent by Pope Agatho, completed the symbol of Chalcedon with an express profession of faith in the two activities and two wills of Christ. Monophysite Christianity still lives on in Egypt and Ethiopia.

Source: Joseph Orlandis (A Short History of the Catholic Church, 2001)