The Fathers of the Fourth Ecumenical Council of Chalcedon (451)
The words “Catholic and Orthodox“, in their common use refer distinctly to the Christian Church of the East and the Roman-Catholic Church of the West. However, these two words refer not only to the geographical difference between the two, but also to their different identities, which emerged after the schism that took place in the 11th century. They also refer to their distinct evolution in history and to the efforts and failures they have made to safeguard the faith of the undivided church promoted by the Seven Ecumenical Councils.
Orthodoxy: derived from the Greek “orthos” and “doxa”. Orthos means right, true, which safeguards the truth. It refers to something that remains constant at all times and does not give in. It is placed alongside the word « doxa » which, in the theological language of the Church, expresses more than an opinion; it expresses the essence of a doctrine, of faith, of a Divine Revelation, of a profession of faith shared by all and which unanimously engenders every person’s allegiance regardless of location or year.
The word “Catholic” derives from the Greek “katholicos”, which means universal and comes from the Greek phrase “kath’holon”, which means “according to the whole” which refers to the all-embracing and universal Roman-Catholic faith, which is present in each local church. The first time the term was used in Christianity dates back to the time of Saint Ignatius of Antioch (years 35- 107 or 113): “Wherever the bishop appears, there let the people be; as wherever Jesus Christ is, there is the Catholic Church” Letter to the Smyrnaeans 8, 2, J.R. Willis translation)
Each local Church expresses the universality of all of Christ’s church, through its profession of faith. This professed fullness of faith ensures that each one of the Churches, located anywhere in the world, is a safeguard of the universal Church because the dogmas of faith that they transmit are faithful restitutions of the dogmas of faith transmitted by the universal Church.
The differences between the dogmas of faith professed by the Orthodox Church and the Roman-Catholic Church
The undivided Church of the first centuries demonstrated its “Catholicity” through the unanimity of its profession of faith. In the centuries that followed, the Roman-Catholic Church introduced new dogmas to the Church’s doctrine of faith. These dogmas were foreign to the theology established by the Council Fathers during the Seven Ecumenical Councils and their content was in opposition with the dogmas professed and claimed by the undivided Church. These new doctrines introduced by Rome were foreign to the Orthodox tradition which safeguards the tradition of the faith as it was established in the Seven Councils and as it was celebrated during the first seven centuries, without changing or adding anything to it. The dogmas of faith promulgated by the Roman-Catholic Church, foreign to the faith established during the Councils and devoid of the universal Church’s approval, are therefore foreign to the Orthodox faith.
The « filioque »
The profession of faith of the Church claims, in the Creed established by the two Ecumenical Councils of Nicaea (325) and of Constantinople (381), the proceeding of the Hypostasis of the Holy Spirit from the Unbegotten Father, the only source of the begetting of the Word and of the proceeding of the Holy Spirit. The “filioque” dogma, introduced in the Spanish church after the Council of Toledo of 589, claims that the Holy Spirit proceeds from the Father and the Son (ex Patre Filioque procedit). This was added to the Nicene Creed and generalized in the Latin Church starting with the 8th century. According to the Orthodox tradition, this goes against Christ’s word in the Gospel of John, which claims that the Holy Spirit proceeds only from the Father and resides within the Son and is given to the world by the Son. In the Lord’s teachings to his disciples before his Passion, he tells them that the Holy Spirit proceeds only from the Father: “But when the Paraclete cometh, whom I will send you from the Father, the Spirit of truth, who proceedeth from the Father, he shall give testimony of me.” (John XV, 26). The Latin filioque, adopted by the Roman-Catholic church in its Creed claims that the Holy Spirit proceeds from the Father and the Son.
The fathers of the Church, such as Basil the Great, Maximos the Confessor and John of Damascus use the phrase “from the Son” (« διά του υιού ») in their theological treaties on the proceeding of the Holy Spirit. Saint Maximos the Confessor wrote in Questions to Thalassius : ““For just as the Holy Spirit exists, by nature, according to substance, as belonging to the Father, so also does he, according to substance, belong to the Son, in that, in an ineffable way, he proceeds substantially from the Father through the begotten Son.” To integrate the phrasing “through the begotten Son”, regarding the mystery of the proceeding of the Holy Spirit, into the trinity doctrine we have to refer to the following theological consideration: the Word, who proceeds from the Father, is undoubtedly contained within the Holy Spirit. Hence, the Father’s Reign is safeguarded; He is the Sole Source of Divinity, who creates the Verb through the Holy Spirit and ineffably sends the Holy Spirit through the Son. “Through” refers here to eternal manifestation, as opposed to eternal proceeding . “ The eternal proceeding of the Holy Spirit through the Son begotten of the Father and the creation of the Son, through the Holy Spirit, within the inscrutable abyss of Divinity remains one of the inscrutable mysteries of the Holy Trinity. This mystery goes beyond any logic and beyond human understanding; the begetting of the Son and the proceeding of the Holy Spirit remain forever sealed and out of the reach of human intelligence.
The Holy Spirit originates from the Father only, through the Son. This means that the Holy Spirit proceeds from the Father only and ineffably through the Son, by the Father’s goodwill. His influence in the world, be it a gift or grace, is transmitted through the Son, this is not to mean that the Holy Spirit is subordinated to the Son, because It shares the same and unique sovereignty, perfection and sanctity “acting on its own and sharing with the Father and the Son infinite and incorruptible power”. The Spirit shines forth and manifests eternally through the Son. It receives Its substance from the Father’s hypostasis and It receives Its eternal manifestation and magnificence from the consubstantial Son. A candle’s flame (i.e. the Holy Spirit) burns because of the candle it was lit on (i.e. the father). It shines through the light reflected by the wick. The flame does by no means originate from the light, but shines forth through it.
One must differentiate between the proceeding of the Holy Spirit from the Father, the Supreme Creator, the Soul Source of the Son and the Holy Spirit and Its eternal shining forth from the Father. Its hypostasis proceeds only from the Father. It resides within the Son and is given to the world through the Son.
Other dogmas professed by the Roman-Catholic Church
Other dogmas of the Roman Catholic Church are: the Immaculate Conception (established on the 8th December 1854 by Pope Pius IX) , papal infallibility (promulgated in 1870), the Assumption of the Virgin Mary (established by Pope Pius XII in 1950) which refers to the bodily taking up of the Virgin Mary into Heaven at the end of her earthly life. These dogmas are professed only by the Catholic Church and are foreign to the Orthodox tradition. Devotion to the Most Sacred Heart of Jesus, which is not a dogma, but a tradition of the Catholic Church, is also foreign to the Orthodox tradition. It was introduced in the 17th century in several dioceses and monasteries in the West. It was first established by Pope Clement the XIII in 1765 and extended to the whole of the Western Church by Pope Pius IXin 1856.
The conciliar character of the Orthodox Church and Roman primacy
Today, we lament doctrinal discrepancies and differences in ecclesiological conception between the Orthodox and the Roman-Catholic Church. These differences were favored by centuries of mutual distancing and disapproval, when the spirit of brotherly love and charity failed. The Crusades also contributed greatly to this environment and the Orthodox community grieved the pillaging of Constantinople in 1204.
As the Byzantine Empire weakened, it became more and more difficult to defend it against invaders and conquerors and this led to its fall in 1453. The Byzantine Empire was weakened by the attacks of the Western European Crusaders and fell easily into the Ottoman invaders hands and was subjected it to their power and authority.
Not even today are the wounds of the past completely healed on the territory which once belonged to the Byzantine Empire. However, due to progress in the relations between the two Churches, there is a growing environment of mutual respect and understanding and we hope that with God’s will the two traditions may one day reconcile and share a unity of faith and harmony that marked the first centuries of Christianity and together don Christ’s seamless garment (John 19, 23-24), the garment of the sole and unique Christian Church.
 Maximos the Confessor, Questions to Thalassius, LXIII, 238, page 296, transl. by Emmanuel Ponsoye, Coll. L’Arbre de Jessé, Les Editions de l’Ancre, Surresnes 1992
 Metochites, VIII, 2, 135, quoted by Yvan Koenig in “Un débat sur le Filioque et l’union avec Rome au XIIIe siècle”.
 From the Orthodox point of view, the Roman dogma of 1854 was an innovation to the teachings of the Fathers of the Church regarding the Immaculate Conception. The Orthodox point of view was summarily expressed in 1857 : “Rome, always young and on the alert, creates and promotes new dogmas that are foreign not only to previous generations, but even to the Apostles and the Fathers […]. This dogma clearly goes against the apostolic writings and the Father’s teachings. How far will this strange re-evaluation of our ancestral tradition go? ”
Anthimus VII of Constantinople made an official statement on the dogma in an Encyclical Letter: “The Church’s dogma states that the supernatural incarnation of the Unique Son and Word of God, through Holy Spirit and the Virgin Mary is the only pure and immaculate incarnation. The papal Church has, however, has introduced another innovation barely forty years ago by establishing a new dogma regarding the immaculate conception of the Virgin Mary, the Mother of God. This dogma was unknown to the traditional Church and was violently fought against by even the most distinguished Papal theologians (Encyclical Letter, Constantinople 1895, p. 11) Quoted by Vassa Kontouma-Conticello in “La question de l’Immaculée Conception dans la tradition orientale“ Conference in the Directory of the Ecole pratique des hautes études, Religious Studies section [118 (2009-2010)] ”
 Patriarchs Demetrios Ist and Bartholomew Ist visited Rome on the 7th December 1987 and respectively June 1995 and assisited the Eucharist celebrated by Pope John Paul the IInd in Sain Peter’s Basilica. Both times, the Pope and the Patriarch present claimed the Creed in Greek (i.e. without the Filioque). Pope John Paul IInd and the Romanian Patriarch Theoctistus did the same in Romanian druing the service held in Rome in the 13th October 2002. The Dominus Iesus, On the Unicity and Salvific Universality of Jesus Christ and the Church declaration published in the 6th August 2000 by the Congregation for the Doctrine of the Faith reflects on the essential teachings of the Church through the Nicaea-Constantinople Creed of 381, again without the Filioque.