History of the Filioque controversy

The history of the Filioque controversy is the historical development of theological controversies within Christianity regarding three distinctive issues: the orthodoxy of the doctrine of procession of the Holy Spirit as represented by the Filioque clause, the nature of anathemas mutually imposed by conflicted sides during the Filioque controversy, and the liceity (legitimacy) of the insertion of the Filoque phrase into the Nicene Creed. Although the debates over the orthodoxy of the doctrine of procession and the nature of related anathemas preceded the question of the admissibility of the phrase as inserted into the Creed, all of those issues became linked when the insertion received the approval of the Pope in the eleventh century.

New Testament 
In  Jesus says of the Holy Spirit: "But when the Helper comes, whom I will send to you from the Father, the Spirit of truth, who proceeds from the Father, he will bear witness about me." In  Jesus also says of the Holy Spirit "he will take what is mine and declare it to you", and it is argued that in the relations between the Persons of the Trinity one Person cannot "take" or "receive" (λήψεται) anything from either of the others except by way of procession.  Texts such as  ("He breathed on them and said: Receive the Holy Spirit"), were seen by Fathers of the Church, especially Athanasius, Cyril of Alexandria and Epiphanius of Cyprus as grounds for saying that the Spirit "proceeds substantially from both" the Father and the Son. Other texts that have been used include ,, , where the Holy Spirit is called "the Spirit of the Son", "the Spirit of Christ", "the Spirit of Jesus Christ", and texts in the Gospel of John on the sending of the Holy Spirit by Jesus (, ,).

Anthony E. Siecienski asserts that it is important to recognize that "the New Testament does not explicitly address the procession of the Holy Spirit as later theology would understand the doctrine." However, he asserts that there are, nonetheless "certain principles established in the New Testament that shaped later Latin Trinitarian theology, and particular texts that both Latins and Greeks exploited to support their respective positions vis-à-vis the filioque." The Orthodox believe that the absence of an explicit mention of the double procession of the Holy Spirit is a strong indication that the filioque is a theologically erroneous doctrine.

The Nicene Creed

The first ecumenical council, that of Nicaea (actual İznik Province, Turkey) [325] ended its Creed with the words "and [sc. I believe] in the Holy Spirit ". The second, that of Constantinople in 381 spoke of the Holy Spirit as "proceeding from the Father" (ἐκ τοῦ Πατρὸς ἐκπορευόμενον). This last phrase is based on  (ὃ παρὰ τοῦ πατρὸς ἐκπορεύεται).

The third ecumenical council, held at Ephesus in 431, which quoted the creed in its 325 form, not in that of 381, decreed in its seventh canon:

While the Council of Ephesus thus forbade setting up a different creed as a rival to that of the first ecumenical council, it was the creed of the second ecumenical council that was adopted liturgically in the East and later a Latin variant was adopted in the West. The form of this creed that the West adopted had two additions: "God from God" (Deum de Deo) and "and the Son" (Filioque).

The fourth ecumenical council, that of Chalcedon (451), quoted the creed of 381 and formally treated it as binding, together with that of 325.  Within 80 years, therefore, the creed of 381 was normative in defining the Christian faith. In the early sixth century, it was widely used in the liturgy in the East and at the end of the same century in parts of the West, perhaps beginning with the Third Council of Toledo in 589.

Possible earliest use in the Creed

Recent discoveries have shown that the earliest known introduction of "and the Son" into the Nicene Creed may have been the work of a local council in the east, the Council of Seleucia-Ctesiphon in Persia in about 410. This was some twenty years before the Nestorian Schism divided the Church in Persia, which after the schism became known as the Church of the East, from the Church in the Roman Empire. The Church of the East does not include "and the Son" in the Creed.

Church fathers

The writings of the early Church Fathers talk sometimes of the Holy Spirit as coming from the Father and the Son. These writings can be used to support either the Latin idea of the procession of the Holy Spirit, or the Orthodox idea.  The writings of the Church fathers, announcing that the Holy Spirit proceeds from the Father and the Son do not necessarily lend their support to either the Catholic position or the Orthodox one. The statement that the Holy Spirit proceeds from the Father and the Son can be used to support either position; that the Spirit comes from the Father and through the Son, or from Father and Son as principal cause.

Yves Cardinal Congar commented, "These pieces of evidence are not sufficient, of course, to form a theological tradition, but they do create a link and a point to an openness. 'The walls of separation do not reach as high as heaven.'"

Before the creed of 381 became known in the West and even before it was adopted by the First Council of Constantinople, Christian writers in the West, of whom Tertullian (c. 160 – c. 220), Jerome (347–420), Ambrose (c. 338 –  397) and Augustine (354–430) are representatives, spoke of the Spirit as coming from the Father and the Son, while the expression “from the Father through the Son” is also found among them.

Tertullian, writing at the beginning of the third century, emphasizes that Father, Son and Holy Spirit all share a single divine substance, quality and power, which he conceives of as flowing forth from the Father and being transmitted by the Son to the Spirit.

One Christian source for Augustine was Marius Victorinus (ca. AD 280–365), who in his arguments against Arians strongly connected the Son and the Spirit.

Hilary of Poitiers, in the mid-fourth century, speaks of the Spirit as "coming forth from the Father" and being "sent by the Son" (De Trinitate 12.55); as being "from the Father through the Son" (ibid. 12.56); and as "having the Father and the Son as his source" (ibid. 2.29); in another passage, Hilary points to John 16.15 (where Jesus says: 'All things that the Father has are mine; therefore I said that [the Spirit] shall take from what is mine and declare it to you'), and wonders aloud whether "to receive from the Son is the same thing as to proceed from the Father" (ibid. 8.20).

Ambrose of Milan, writing in the 380s, openly asserts that the Spirit "proceeds from (procedit a) the Father and the Son", without ever being separated from either (On the Holy Spirit 1.11.20).

None of these writers, however, makes the Spirit's mode of origin the object of special reflection; all are concerned, rather, to emphasize the equality of status of all three divine persons as God, and all acknowledge that the Father alone is the source of God's eternal being."

Procession of the Holy Spirit

Already in the fourth century the distinction was made, in connection with the Trinity, between the two Greek verbs  ἐκπορεύεσθαι (the verb used in the original Greek text of the 381 Nicene Creed) and προϊέναι. In his Oration on the Holy Lights (XXXIX), Saint Gregory of Nazianzus wrote: "The Holy Ghost is truly Spirit, coming forth (προϊέναι) from the Father indeed, but not after the manner of the Son, for it is not by Generation but by Procession (ἐκπορεύεσθαι)".

That the Holy Spirit "proceeds" from the Father and the Son in the sense of the Latin word procedere and the Greek προϊέναι (as opposed to the Greek ἐκπορεύεσθαι) was taught by the early fifth century by Saint Cyril of Alexandria in the East, the Athanasian Creed (probably of the middle of the fifth century), and a dogmatic epistle of Pope Leo I, who declared in 446 that the Holy Spirit proceeds from both Father and Son.

Although the Eastern Fathers were aware that in the West the procession of the Holy Spirit from the Father and the Son was taught, they did not generally regard it as heretical: "a whole series of Western writers, including popes who are venerated as saints by the Eastern church, confess the procession of the Holy Spirit also from the Son; and it is even more striking that there is virtually no disagreement with this theory."

The phrase Filioque first appears as an anti-Arian interpolation in the Creed at the Third Council of Toledo (589), at which Visigothic Spain renounced Arianism, accepting Catholic Christianity. The addition was confirmed by subsequent local councils in Toledo and soon spread throughout the West, not only in Spain, but also in the kingdom of the Franks, who had adopted the Catholic faith in 496, and in England, where the Council of Hatfield imposed it in 680 as a response to Monothelitism. However, it was not adopted in Rome.

A number of Church Fathers of the 4th and 5th centuries explicitly speak of the Holy Spirit as proceeding "from the Father and the Son". They include Hilary of Poitiers (c. 300 – c. 368), Ephrem the Syrian (c. 306 – 373), Epiphanius of Salamis(c. 310–320 – 403), Ambrose (337–340 – 397),
Augustine of Hippo (354 – 430), Cyril of Alexandria (c. 376–444), and Pope Leo I (c. 400–461). In the 7th century, Saint Maximus the Confessor (c. 580 – 662) declared it wrong to make accusations against the Romans for saying that the Holy Spirit proceeds also from the Son, since the Romans were able to cite the unanimous support of the Latin Fathers and a statement by Saint Cyril of Alexandria. Apart from those already mentioned, these Latin Fathers included Saints Faustus of Riez (died between 490 and 495), Gennadius of Massilia (died c. 496), Avitus of Vienne (c. 470 – 523), Fulgentius of Ruspe (462 or 467 – 527 or 533), and Isidore of Seville (died 636).

"From the Father through the Son"
Church Fathers also use the phrase "from the Father through the Son". The Roman Catholic Church accepts both phrases, and considers that they do not affect the reality of the same faith and instead express the same truth in slightly different ways. The influence of Augustine of Hippo made the phrase "proceeds from the Father through the Son" popular throughout the West but, while used also in the East, "through the Son" was later, according to Philip Schaff, dropped or rejected by some as being nearly equivalent to "from the Son" or "and the Son". Others spoke of the Holy Spirit proceeding "from the Father", as in the text of the Nicaeno-Constantinopolitan Creed, which "did not state that the Spirit proceeds from the Father alone".

Hilary of Poitiers

Hilary of Poitiers is one of "the chief patristic source(s) for the Latin teaching on the filioque."  However, Siecienski notes that "there is also reason for questioning Hilary's support for the filioque as later theology would understand it, especially given the ambiguous nature of (Hilary's) language as it concerns the procession."

Ambrose of Milan

Ambrose of Milan, though "firmly rooted in Eastern tradition", was nonetheless "one of the earliest witnesses to the explicit affirmation of the Spirit's procession from the Father and the Son".

Jerome

Siecienski characterizes Jerome's views on the procession of the Holy Spirit as "defying categorization".  His name is often included in Latin florilegia as a supporter of the filioque and Photius even felt called to defend Jerome's reputation against those who invoked him in support of the doctrine.  However, because Jerome's writing contains scant references to the doctrine and even those are "far from ambiguous affirmations of a double procession", Orthodox theologians such as John Meyendorff have argued that he "could hardly be regarded a proponent of the filioque".

Augustine of Hippo

Augustine's writings on the Trinity became the foundation of Latin trinitarian theology and serves as the foundation for the doctrine of the filioque.

Pope Leo I

Siecienski characterizes the writings of Pope Leo I on the subject of the procession of the Holy Spirit as a "sword that cuts both ways" in that "his writings would later be used by both Latins and Greeks to support their respective positions."

Pope Gregory the Great

Pope Gregory the Great is usually counted as a supporter of the Spirit's procession from the Father and the Son, despite the fact that Photius and later Byzantine theologians counted him as an opponent of the doctrine. Siecienski attributes this apparent contradiction to two factors: Gregory's "loose and unguarded language" regarding the procession and differences between the original Latin text of Gregory's Dialogues and Pope Zacharias' Greek translation of them. Gregory's text, in Latin, clearly affirmed the Filioque, but Zacharias' translation into Greek used the phrase "abiding in the Son" rather than "proceeding from the Son", thus leading later Byzantine clerics to assert that Gregory did not support double procession.

First Eastern opposition

In 638, the Byzantine emperor Heraclius, with the support of or at the instigation of Patriarch Sergius I of Constantinople, published the Ecthesis, which defined as the official imperial form of Christianity Monothelitism, the doctrine that, while Christ possessed two natures, he had only a single will. This was widely accepted in the East, but before the Ecthesis reached Rome, Pope Honorius I, who had seemed to support Monothelitism, died, and his successor Pope Severinus condemned the Ecthesis outright, and so was forbidden his seat until 640. His successor Pope John IV also rejected the doctrine completely, leading to a major schism between the eastern and western halves of the Chalcedonian Church, which was healed when the doctrine of the Ecthesis was condemned.

Meanwhile, in Africa, an Eastern monk named Maximus the Confessor carried on a furious campaign against Monothelitism, and in 646 he convinced the African councils to draw up a manifesto against the doctrine. This they forwarded to the new pope Theodore I, who in turn wrote to Patriarch Paul II of Constantinople, outlining the heretical nature of the doctrine. Paul, a devoted Monothelite, replied in a letter directing the Pope to adhere to the doctrine of one will. Theodore in turn excommunicated the Patriarch in 649, declaring him a heretic, after Paul, in 647 or 648, had issued in the name of Emperor Constans II an edict known as the Typos, which banned any mention of either one or two activities or wills in Christ. The Typos, instead of defusing the situation, made it worse by implying that either doctrine was as good as the other. Theodore planned the Lateran Council of 649 but died before he could convene it, which his successor, Pope Martin I, did. The Council condemned the Ecthesis and the Typos, and Pope Martin wrote to Constans, informing the emperor of its conclusions and requiring him to condemn both the Monothelite doctrine and his own Typos. Constans responded by having Pope Martin abducted to Constantinople, where he was tried and condemned to banishment and died as a result of the torture to which he had been subjected. Maximus also was tried and banished after having his tongue and his hand cut off.

It was in this context of conflict between East and West that the Monothelite Patriarch Paul of Constantinople made accusations against Pope Theodore of Rome for speaking of the Holy Spirit as proceeding from the Father and the Son. Pope Theodore's expression was in a letter that he wrote, not in the Creed, which was not yet used liturgically in Rome.

Maximus the Confessor wrote a letter in defence of the expression used by the Pope.
The words with which Saint Maximus the Confessor (c. 580 – 13 August 662) declared that it was wrong to condemn the Roman use of Filioque are as follows:
"They [the Romans] have produced the unanimous evidence of the Latin Fathers, and also of Cyril of Alexandria, from the study he made of the gospel of St John. On the basis of these texts, they have shown that they have not made the Son the cause of the Spirit – they know in fact that the Father is the only cause of the Son and the Spirit, the one by begetting and the other by procession –but that they have manifested the procession through him and have thus shown the unity and identity of the essence. They [the Romans] have therefore been accused of precisely those things of which it would be wrong to accuse them, whereas the former [the Byzantines] have been accused of those things it has been quite correct to accuse them [Monothelitism]."

Later developments
Widespread use of the Filioque in the West led to controversy with envoys of the Byzantine Emperor Constantine V at a synod held at Gentilly in 767. The use of Filioque was defended by Saint Paulinus II, the Patriarch of Aquileia, at the Synod of Friuli, Italy in 796, and it was endorsed in 809 at the local Council of Aachen. At the beginning of ninth century in 808, John, a Greek monk of the monastery of St. Sabas, charged the monks of Mt. Olivet with heresy, since they had inserted the Filioque into the Creed.

As the practice of chanting the Latin Credo at Mass spread in the West, the Filioque became a part of the Latin rite liturgy. This practice was adopted in Emperor Charlemagne's court in 798 and spread through his empire, but which, although it was in use in parts of Italy by the eighth century, was not accepted in Rome until 1014. In response, the theology of the Filioque was expressed in the 809 local Council of Aachen.

Photian controversy

Later again around 860AD the controversy over the Filioque and the Frankish monks broke out in the course of the disputes between Saint Photius and Patriarch Ignatius of Constantinople.  In 867, Photius was Patriarch of Constantinople and issued an Encyclical to the Eastern Patriarchs, and called a council in Constantinople in which he charged the Western Church with heresy and schism because of differences in practices, in particular for the Filioque and the authority of the Papacy. This moved the issue from jurisdiction and custom to one of dogma. This council declared Pope Nicholas anathema, excommunicated and deposed.

Photius excluded not only "and the Son" but also "through the Son" with regard to the eternal procession of the Holy Spirit: for him "through the Son" applied only to the temporal mission of the Holy Spirit (the sending in time). He maintained that the eternal procession of the Holy Spirit is "from the Father alone". This phrase was verbally a novelty. However, Orthodox theologians generally hold that in substance the phrase was only a reaffirmation of traditional teaching. Sergei Bulgakov, on the other hand, declared that Photius's doctrine itself "represents a sort of novelty for the Eastern church".

Photius's importance endured in regard to relations between East and West. He is recognized as a Saint by the Eastern Orthodox Church and his line of criticism has often been echoed later, making reconciliation between East and West difficult.

At least three councils (867, 869, 879) where held in Constantinople over the deposition of Ignatius by Emperor Michael III and his replacement by Photius.  The Council of Constantinople 867 was convened by Photius, so to address the question of Papal Supremacy over all of the churches and their patriarchs and the use of the filioque.

The council of 867 was followed by the Council of Constantinople 869, which reversed the previous council and was promulgated by Rome. The Council of Constantinople in 879 restored Photius to his see. It was attended by Western legates Cardinal Peter of St Chrysogonus, Paul Bishop of Ancona and Eugene Bishop of Ostia who approved its canons, but it is unclear whether it was ever promulgated by Rome.

Adoption in the Roman Rite
It was only in 1014, at the request of the German King Henry II who had come to Rome to be crowned Emperor and was surprised at the different custom in force there, that Pope Benedict VIII, who owed to Henry his restoration to the papal throne after usurpation by Antipope Gregory VI, had the Creed, with the addition of Filioque, sung at Mass in Rome for the first time.

Since then the Filioque phrase has been included in the Creed throughout all the Latin Rite except where Greek is used in the liturgy, although it was never adopted by Eastern Catholic Churches.

East-West schism

Eastern opposition to the Filioque strengthened with the East-West Schism of 1054. Two councils were held to heal the break discussed the question.

The Second Council of Lyon (1274) accepted the profession of faith of Emperor Michael VIII Palaiologos in the Holy Spirit, "proceeding from the Father and the Son" and the Greek participants, including Patriarch Joseph I of Constantinople sang the Creed three times with the Filioque addition. Most Byzantine Christians feeling disgust and recovering from the Latin Crusaders' conquest and betrayal, refused to accept the agreement made at Lyon with the Latins. In 1282, Emperor Michael VIII died and Patriarch Joseph I's successor, John XI, who had become convinced that the teaching of the Greek Fathers was compatible with that of the Latins, was forced to resign, and was replaced by Gregory II, who was strongly of the opposite opinion.

The council required Eastern churches wishing to be reunited with Rome to accept the Filioque as a legitimate expression of the faith, while it did not require those Christians to change the recitation of the creed in their liturgy.

The council of Lyons also condemned "all who presume to deny that the holy Spirit proceeds eternally from the Father and the Son, or rashly to assert that the holy Spirit proceeds from the Father and the Son as from two principles and not as from one. "

Another attempt at reunion was made at the fifteenth-century Council of Florence, to which Emperor John VIII Palaiologos, Ecumenical Patriarch Joseph II of Constantinople, and other bishops from the East had gone in the hope of getting Western military aid against the looming Ottoman Empire. Thirteen public sessions held in Ferrara from 8 October to 13 December 1438 the Filioque question was debated without agreement. The Greeks held that any addition whatever, even if doctrinally correct, to the Creed had been forbidden by the Council of Ephesus, while the Latins claimed that this prohibition concerned meaning, not words.

During the council of Florence in 1439, accord continued to be elusive, until the argument prevailed among the Greeks themselves that, though the Greek and the Latin saints expressed their faith differently, they were in agreement substantially, since saints cannot err in faith; and by 8 June the Greeks accepted the Latin statement of doctrine. On 10 June Patriarch Joseph II died. A statement on the Filioque question was included in the Laetentur Caeli decree of union, which was signed on 5 July 1439 and promulgated the next day, with Mark of Ephesus being the only bishop to refuse his signature.

The Eastern Church refused to consider the agreement reached at Florence binding, since the death of Joseph II had for the moment left it without a Patriarch of Constantinople. There was strong opposition to the agreement in the East, and when in 1453, 14 years after the agreement, the promised military aid from the West still had not arrived and Constantinople fell to the Turks, neither Eastern Christians nor their new rulers wished union between them and the West.

Council of Jerusalem in 1583 AD

The 1583 Synod of Jerusalem condemned those who do not believe the Holy Spirit proceeds from the Father alone in essence, and from Father and Son in time. In addition, this synod re-affirmed adherence to the decisions of Council of Nicaea I in AD 325.

Council of Jerusalem in 1672 AD

In 1672, an Eastern Orthodox council was held in Jerusalem, presided by patriarch Dositheos Notaras. Council re-affirmed procession of the Holy Spirit from the Father alone.

Recent discussion
Orthodox theologian Vasily Bolotov published in 1898 his "Thesen über das Filioque", in which he maintained that the Filioque, like Photios's "from the Father alone", was a permissible theological opinion (a theologoumenon, not a dogma) that cannot be an absolute impediment to reestablishment of communion. This thesis was supported by Orthodox theologians Sergei Bulgakov, Paul Evdokimov and I. Voronov, but was rejected by Vladimir Lossky.

Several Orthodox theologians have considered the Filioque anew, with a view to reconciliation of East and West.Theodore Stylianopoulos provided in 1986 an extensive, scholarly  overview of the contemporary discussion. Twenty years after writing the first (1975) edition of his  book, The Orthodox Church, Metropolitan Kallistos of Diokleia said that he had changed his mind and had concluded that "the problem is more in the area of semantics and different emphases than in any basic doctrinal differences": "the Holy Spirit proceeds from the Father alone" and "the Holy Spirit proceeds from the Father and the Son" may both have orthodox meanings if the words translated "proceeds" actually have different meanings. For some Orthodox, then, the Filioque, while still a matter of conflict, would not impede full communion of the Roman Catholic and Orthodox Churches if other issues were resolved. But many Orthodox consider that the Filioque is in flagrant contravention of the words of Christ in the Gospel,. has been specifically condemned by the Orthodox Church, and remains a fundamental heretical teaching which divides East and West.

Eastern Orthodox Christians also object that, even if the teaching of the Filioque can be defended, its interpolation into the Creed is anti-canonical. The Roman Catholic Church, which like the Eastern Orthodox Church considers the teaching of the Ecumenical Councils to be infallible, "acknowledges the conciliar, ecumenical, normative and irrevocable value, as expression of the one common faith of the Church and of all Christians, of the Symbol professed in Greek at Constantinople in 381 by the Second Ecumenical Council. No profession of faith peculiar to a particular liturgical tradition can contradict this expression of the faith taught and professed by the undivided Church", but considers permissible additions that elucidate the teaching without in any way contradicting it, and that do not claim to have, on the basis of their insertion, the same authority that belongs to the original. It allows liturgical use of the Apostles' Creed as well of the Nicene Creed, and sees no essential difference between the recitation in the liturgy of a creed with orthodox additions and a profession of faith outside the liturgy such that of the Patriarch of Constantinople Saint Tarasius, who developed the Nicene Creed as follows: "the Holy Spirit, the Lord and giver of life, who proceeds from the Father through the Son".

Some theologians have even envisaged as possible acceptance of Filioque by the Eastern Orthodox Church (Vladimir Lossky) or of "from the Father alone" by the Roman Catholic Church (André de Halleux).

The Roman Catholic view that the Greek and the Latin expressions of faith in this regard are not contradictory but complementary has been expressed as follows:

At the outset the Eastern tradition expresses the Father's character as first origin of the Spirit. By confessing the Spirit as he "who proceeds from the Father", it affirms that he comes from the Father through the Son. The Western tradition expresses first the consubstantial communion between Father and Son, by saying that the Spirit proceeds from the Father and the Son (Filioque). … This legitimate complementarity, provided it does not become rigid, does not affect the identity of faith in the reality of the same mystery confessed.

For this reason, the Roman Catholic Church has refused the addition of καὶ τοῦ Υἱοῦ to the formula ἐκ τοῦ Πατρὸς ἐκπορευόμενον of the Nicene Creed in the Churches, even of Latin rite, which use it in Greek with the Greek verb "έκπορεύεσθαι".

At the same time, the Eastern Catholic Churches, although they do not use the Filioque in the Creed, are in full communion with Rome, which accepts the Filioque in both liturgy and dogma.

Importance of Saint Maximus in ecumenical relations
The study published by the Pontifical Council for Promoting Christian Unity says that, according to Saint Maximus, the phrase "and from the Son" does not contradict the Holy Spirit's procession from the Father as first origin (ἐκπόρευσις), since it concerns only the Holy Spirit's coming (in the sense of the Latin word processio and Saint Cyril of Alexandria's προϊέναι) from the Son in a way that excludes any idea of subordinationism.

Orthodox theologian and Metropolitan of Pergamon, John Zizioulas, says: "For Saint Maximus the Filioque was not heretical because its intention was to denote not the ἐκπορεύεσθαι (ekporeuesthai) but the προϊέναι (proienai) of the Spirit."

Metropolitan John Zizioulas also wrote:
"As Saint Maximus the Confessor insisted, however, in defence of the Roman use of the Filioque, the decisive thing in this defence lies precisely in the point that in using the Filioque the Romans do not imply a "cause" other than the Father. The notion of "cause" seems to be of special significance and importance in the Greek Patristic argument concerning the Filioque. If Roman Catholic theology would be ready to admit that the Son in no way constitutes a "cause" (aition) in the procession of the Spirit, this would bring the two traditions much closer to each other with regard to the Filioque." This is precisely what Saint Maximus said of the Roman view, that "they have shown that they have not made the Son the cause of the Spirit– they know in fact that the Father is the only cause of the Son and the Spirit, the one by begetting and the other by procession".

In this regard, the letter of the Pontifical Council for Promoting Christian Unity on "The Greek and the Latin Traditions regarding the Procession of the Holy Spirit" upholds the monarchy of the Father as the "sole Trinitarian Cause [aitia] or principle [principium] of the Son and the Holy Spirit" While the Council of Florence proposed the equivalency of the two terms "cause" and "principle" and therefore implied that the Son is a cause (aitia) of the subsistence of the Holy Spirit, the letter of the Pontifical Council distinguishes
between what the Greeks mean by 'procession' in the sense of taking origin from, applicable only to the Holy Spirit relative to the Father (ek tou Patros ekporeuomenon), and what the Latins mean by 'procession' as the more common term applicable to both Son and Spirit (ex Patre Filioque procedit; ek tou Patros kai tou Huiou proion). This preserves the monarchy of the Father as the sole origin of the Holy Spirit while simultaneously allowing for an intratrinitarian relation between the Son and Holy Spirit that the document defines as 'signifying the communication of the consubstantial divinity from the Father to the Son and from the Father through and with the Son to the Holy Spirit'."

Roman Catholic theologian Avery Dulles, writing of the Eastern fathers who, while aware of the currency of theFilioque in the West, did not generally regard it as heretical, said: "Some, such as Maximus the Confessor, a seventh-century Byzantine monk, defended it as a legitimate variation of the Eastern formula that the Spirit proceeds from the Father through the Son."

Michael Pomazansky and John Romanides hold that Maximus' position does not defend the actual way the Roman Catholic Church justifies and teaches the Filioque as dogma for the whole church. While accepting as a legitimate and complementary expression of the same faith and reality the teaching that the Holy Spirit proceeds from the Father through the Son. Maximus held strictly to the teaching of the Eastern Church that "the Father is the only cause of the Son and the Spirit" and wrote a special treatise about this dogma. Later again at the Council of Florence in 1438, the West held that the two views were contradictory.

Greek verbs translated as "proceeds"

In 1995 the Pontifical Council for Promoting Christian Unity published in various languages a study on The Greek and the Latin Traditions regarding the Procession of the Holy Spirit, which pointed out an important difference in meaning between the Greek verb ἐκπορεύεσθαι and the Latin verb procedere, both of which are commonly translated as "proceed". The pontifical council stated that the Greek verb ἐκπορεύεσθαι indicates that the Spirit "takes his origin from the Father ... in a principal, proper and immediate manner", while the Latin verb, which corresponds rather to the verb προϊέναι in Greek, can be applied to proceeding even from a mediate channel.

Metropolitan John Zizioulas, while maintaining the explicit Orthodox position of the Father as the single origin and source of the Holy Spirit, has declared that the recent document the Pontifical Council for Promoting Christian Unity shows positive signs of reconciliation. Zizioulas states "Closely related to the question of the single cause is the problem of the exact meaning of the Son's involvement in the procession of the Spirit. Saint Gregory of Nyssa explicitly admits a 'mediating' role of the Son in the procession of the Spirit from the Father. Is this role to be expressed with the help of the preposition δία (through) the Son (εκ Πατρός δι'Υιού), as Saint Maximus and other Patristic sources seem to suggest?"

Zizioulas continues with "The Vatican statement notes that this is 'the basis that must serve for the continuation of the current theological dialogue between Catholic and Orthodox'. I would agree with this, adding that the discussion should take place in the light of the 'single cause' principle to which I have just referred." Zizioulas continues with saying that this "constitutes an encouraging attempt to clarify the basic aspects of the 'Filioque' problem and show that a rapprochement between West and East on this matter is eventually possible".

John Romanides too, while personally opposing the "Filioque", has stated that in itself, outside the Creed, the phrase is not considered to have been condemned by the 878–880 Council of Constantinople, "since it did not teach that the Son is 'cause' or 'co-cause' of the existence of the Holy Spirit"; however, it could not be added to the Creed, "where 'procession' means 'cause' of existence of the Holy Spirit".

Joint statement in the United States in 2003
The Filioque was the main subject discussed at the 62nd meeting of the North American Orthodox-Catholic Theological Consultation, in June 2002. In October 2003, the Consultation issued an agreed statement, The Filioque: A Church-Dividing Issue?, which provides an extensive review of Scripture, history, and theology.  The recommendations include:

That all involved in such dialogue expressly recognize the limitations of our ability to make definitive assertions about the inner life of God.
That, in the future, because of the progress in mutual understanding that has come about in recent decades, Orthodox and Catholics refrain from labeling as heretical the traditions of the other side on the subject of the procession of the Holy Spirit.
That Orthodox and Catholic theologians distinguish more clearly between the divinity and hypostatic identity of the Holy Spirit (which is a received dogma of our Churches) and the manner of the Spirit's origin, which still awaits full and final ecumenical resolution.
That those engaged in dialogue on this issue distinguish, as far as possible, the theological issues of the origin of the Holy Spirit from the ecclesiological issues of primacy and doctrinal authority in the Church, even as we pursue both questions seriously, together.
That the theological dialogue between our Churches also give careful consideration to the status of later councils held in both our Churches after those seven generally received as ecumenical.
That the Catholic Church, as a consequence of the normative and irrevocable dogmatic value of the Creed of 381, use the original Greek text alone in making translations of that Creed for catechetical and liturgical use.
That the Catholic Church, following a growing theological consensus, and in particular the statements made by Pope Paul VI, declare that the condemnation made at the Second Council of Lyons (1274) of those "who presume to deny that the Holy Spirit proceeds eternally from the Father and the Son" is no longer applicable.

In the judgment of the consultation, the question of the Filioque is no longer a "Church-dividing" issue, which would impede full reconciliation and full communion.  It is for the bishops of the Catholic and Orthodox Churches to review this work and to make whatever decisions would be appropriate.

See also 
 Papal infallibility Catholic dogma

Notes and references
Notes

Citations

Bibliography

Much has been written on the Filioque; what follows is selective.

 

 See esp. pp. 75–79, for a summary of Congar's work on the Filioque.  Congar is widely considered the most important Roman Catholic ecclesiologist of the twentieth century. He was influential in the composition of several Vatican II documents. Most important of all, he was instrumental in the association in the West of pneumatology and ecclesiology, a new development.
 A close examination of Karl Barth's defense of the filioque and why his position is closer to an Eastern perspective than has typically been assumed.
 

 
 
 An apologetic response to polemical attacks.  A useful book for its inclusion of important texts and documents; see especially citations and works by Thomas Aquinas, O.P., Demetrios Kydones, Nikos A. Nissiotis, and Alexis Stawrowsky. The select bibliography is excellent.  The author demonstrates that the Filioque dispute is only understood as part of a dispute over papal primacy and cannot be dealt with apart from ecclesiology.

. Reconsideration of the views of Aquinas, especially on deification and grace, as well as his Orthodox critics.  The author suggests that Aquinas may have a more accurate perspective than his critics, on the systematic questions of theology that relate to the Filioque dispute.

 
 

 

 This work is still valuable for understanding cultural and theological estrangement of East and West by the turn of the millennium.  Now, it is evident that neither side understood the other; both Greek and Latin antagonists assumed their own practices were normative and authentic.

External links 
 The Greek and Latin Traditions Regarding the Procession of the Holy Spirit
 Joint North American Orthodox-Catholic Statement
 Filioque at OrthodoxWiki
 full-length article at OrthodoxAnswers.org
 
 Christian Cyclopedia entry
Agreed statement of the North American Orthodox-Catholic Theological Consulation
 An Orthodox Response to the Filioque – Zizioulas
 The Procession of the Holy Spirit in Orthodox Trinitarian Doctrine by V. Lossky

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