What is the relationship between the Eastern Catholic Churches and the Orthodox Church?
In general, the Eastern Catholic Churches are portions of the Orthodox Churches that broke off for one or more reasons and came into communion with the Roman Catholic Church. The exceptions are the Italo-Albanian Church and the Maronites. The Italo-Albanian Church was founded in Italy and remained there, never breaking communion with the Roman Catholic Church. Tradition holds that the Maronites, too, were never out of communion with Rome even though they were located in the Middle East.
Because the Eastern Catholic Churches did break away from the Orthodox Churches and, thereby, broke communion with their “mother Church,” it follows that there is some tension between them. Working relations between then tend to be good, especially in areas where the two can support charitable outreach missions.
In the Middle East, the relationship between the Melkite and Antiochian Churches is less strained. In fact, a degree of (unofficial) intercommunion is found there. Since small villages might have only a Melkite or an Antiochian parish, the people from any given village simply go to the church that is there. If they are in another village, they will go to that church, and whether it is Orthodox or Catholic doesn’t seem to enter into the picture.
This has led some Melkite bishops to take a leading role in trying to find a common ground for reunion. One such proposal, rejected by both Rome and Orthodox, was that the Melkite Church come into communion with both Orthodoxy and Rome, which would allow the Melkites to form a bridge. This role of bridge builder is, in fact, one that the Melkites have taken on. Melkite patriarchs have consistently said that they are the voice of the Orthodox in Rome.
How do the Eastern Catholic Churches differ from each other?
To answer this question we have to treat the differences among the churches of a given Rite and then look at the differences among the Rites. Having said that, let’s see what we can address.
As we noted in a previous question, there are differences of language, musical settings, and some minor liturgical variations in the churches of the Byzantine Rite. The same is true for all of the other Rites except the Armenian. Since the Armenian Church and the Armenian Rite are one and the same, it follows that there are no variations there.
Within the Syriac Rite, the Maronites have a particular liturgy that itself varies by season fo the year and is different from the Syro-Malabar and Syro-Malankara Churches. The latter two, both Indian Churches, are very similar and differ in virtually nothing. Historical records of these two churches have been lost, but attempts are currently being made to reconstruct the Liturgy of the early church.
The Alexandrian Churches are quite different, but primarily for cultural reasons. The Ge’ez Church found in Ethiopia uses the Alexandrian Rite, which derives from the Divine Liturgy of Saint Mark. However, the church uses the ancient language of Ethiopia called Ge’ez. Historical records for this church have, sadly, bee lost, and it is impossible to reconstruct the earliest form of worship there. The Coptic Catholic Church uses a liturgy that is a modified version of the Divine Liturgy of Saint Basil.
Beyond these minor differences, there are differences of government based upon the type of church – whether it has a patriarch, a metropolitan archbishop, or no head at all.
Theologically, there are no differences, although, again, there may be a “difference of expression,” meaning that how something is explained may differ from church to church.
Excerpt from Faulk, Edward. 101 Questions and Answers on Eastern Catholic Churches. (Paulist Press: Mahwah, NJ) 2007.