What are the main differences between the Roman Catholic and Eastern Orthodox Churches?

I was told that as a Catholic if I were to go to say a Greek Orthodox church I would have technically fulfilled my obligation to go to mass. Is this true? Also what are the main differences between the two? I know originally they were one but through time the east and west slowly changed on views of certain things until the complete schism in 1054. What exactly are the differences? Like do we have more in common with the Orthodox churches than say Protestant denominations?

I won’t go into the differences between our Churches because it’s above my pay grade.

As far as fulfilling Mass obligation: while their liturgies are true, they do not fulfill our obligation.

Canon 1248 §1. A person who assists at a Mass celebrated anywhere in a Catholic rite either on the feast day itself or in the evening of the preceding day satisfies the obligation of participating in the Mass.

We are not in communion with the Orthodox churches, and while their liturgies are ancient and express a true sacrifice just like ours, I would say that because they are not in union with Rome and do not pray for the Pope - this does not count as a “Catholic rite”. Others may be able to elaborate on this more or express it more accurately than me.

If an Orthodox Church is the only option you have (with no Catholic alternative), then while it may or may not be appropriate to attend their liturgy depending on one’s individual situation, a Catholic shouldn’t receive there and in any case their obligation to attend Mass is abrogated because there is not reasonable Catholic option.

The main differences are as follows :

Papal infallibility
Papal supremacy
Immaculate Conception of Mary
Development of doctrine

Hope that helps

No, it is not true.

There are many books on this topic. It’s complex. I suggest you do some reading and then come back with specific questions.

This is a complicated issue, but certainly your last question would be answered “yes”.

There is a huge common ground. Vatican II refers to the Orthodox “churches”, whereas other Christians are recognized as having something similar (and identified as valuable at the council). Most Marian beliefs and devotions are compatible, as are the sacraments. Refer to what St. JP II wrote about the 2 “lungs” of the Church, east and west. Also, in our time the EO stand side by side with the RCC on issues like Prolife and Sanctity of Marriage. Some Protestants also are at our side, but at least half are not.

This is not to minimize the significant differences that remain.

While this issue is on our minds, why not take a moment for all of us to pray for unity between Catholics and Orthodox?

Do what 1ke said… read some books on it. This topic is like opening a can of worms. It can be great sometimes, but for the most part, it’s just a mess to pick up.

Here is a “difference” article from the view point of an Orthodox priest. Too long to post. Link

Of course, check Roman Catholic writers as well.

I think there’s a lot of value in the “above my pay grade” responses.

I’ve studied the differences quite a lot over the years. The main conclusion I have come to is: if somehow it turns out that I’m really Orthodox, then I’m am not going to switch to Catholicism – but that doesn’t mean I’m going to convert to Orthodoxy either.

So basically I don’t worry to much about the differences between Catholic and Orthodox (or, for that matter, OO, ACoE, PNCC, Anglican, Lutheran …).

The Roman Catholic God is a God of “savants and philosophers”? Please. This is a caricature of the Catholic Faith. Rome does not teach that you have to be some kind of philosopher to know God. Catholicism is for the common people too and let’s not forget, the fathers of the Church were humans and consequently fallible. They by no means have the last word. Also, God did not give the apostles the complete faith. The dogma of the trinity was a development and so was the doctrine of the two natures of Christ. They did not just come out of the sky like a meteor. Eastern Orthodoxy is itself a result of development.

Well said. Don’t underestimate God’s perspicacity - he knows a sheep when he sees one, as do most of us if we are honest about it. Not that hard. Sometimes Christianity in its true form is just too simple for us…too stark. Theology is much more interesting.

I’ll just focus on the services/mass.

Catholics believe we have valid sacraments and our liturgy is good. The problem arises on the Orthodox end. Most Orthodox priests won’t give you communion, although a larger number might be willing to hear your confession (which is unrelated to mass). Meanwhile, Catholics are much more willing to give us Orthodox communion at their services. Orthodox services however have the antidoron, which is unconsecrated bread. This bread is for everyone, including non-Christians and those Orthodox who did not feel called to the Eucharist. As a former Catholic, I would at least say that attending an Orthodox service is better than no service, even if you are unable to receive communion.

Another issue is that a large number of Orthodox churches don’t use English in their services, although a number of such churches are making the transition by using both English and Greek. Chances are, if you encounter an Antiochan Orthodox Church, they will use English. If it is Greek, I’d say the chances are around 50-50 for exclusive Greek use.

As for commonalities between Catholic and Orthodox vs. Catholic and Protestants, it really depends upon the denomination of Protestantism. If you speak of something like Pentecostals, then yes, Catholics have more in common with us. If you are talking about the Anglican Church, then Catholics would have more in common with the Anglicans than they would the Orthodox. These are just a few examples, but it should give you a good framework.

I find that statement very difficult to accept in view of changes in some parts of the Anglican Communion in recent decades.

Apostasy of those minority groups aside, I think it’s an objectively true statement, and I think most Orthodox would agree with it. I think Catholics don’t tend to accept that because they have a particular bone to pick with Protestants, not because of the facts. I’ve heard the Orthodox refer to Catholics and Protestants as two sides of the same coin. Implying they are working with a different currency.

But that may be changing slightly, as some Anglican provinces could soon drop the filioque from the Creed.

What is so funny is when someone says “Anglican” I am like, yeah, love 'em - not so much when someone says “Episcopalian.” Kind of like “British” and “English” (yes I know the difference; not talking geography here). When I say “Anglican” I think Cardinal Newman, T.S. Eliot, etc. that Church of England. And, yes I do think Catholics have more in common with that Church than Orthodox - only problem is that that Anglican Church doesn’t really exist anymore - maybe in Africa (:)), a handful of people in Britain, US, Australia, Canada, etc.

There are a lot of Orthodox converts in the West, but I don’t know how much empathy they have with the Catholic Church (or knowledge for that matter - this varies widely). As a result I am not sure how much empathy Catholics have with the converts - probably much more with the “cradle” Greek Orthodox would be my guess.

This ^^ just reminds us that there’s bias on both sides.

I want to retract my previous post; it states the “priest” who wrote that piece was part of the “American Orthodox Church,” which I highly doubt is a canonical Orthodox jurisdiction. If so, it would be like reading about Roman Catholicism from the Society of Saint Pius V or other sedevacantist groups.

Instead, I am going to direct the OP to the sight of the Orthodox Church of America: Orthodoxy and Roman Catholicism. And, they are far more charitable than the previous source.

I sincerely apologize for the error. And, also to repeat, research both Orthodox and Roman Catholic sources.

The OCA (Orthodox Church in America) is and isn’t canonical. It depends upon which Orthodox you ask. If you ask a Russian Orthodox, they will say it is canonical, because it was Moscow that granted them their own autonomy/autocephaly. The OCA used to be part of the ROC, long story short. If you ask a Greek Orthodox, they will deny it because according to them, at least, only the Patriarch of Constantinople has the power to grant autocephaly. It’s a contentious issue of proper jurisdiction. But it isn’t anything as significant or serious as the sedevacantists of Catholicism.

It should be clarified that (hopefully) you are only referring to the Roman Rite of the Church. Eastern Catholic churches follow the Orthodox practices you mentioned (antidoron and language).

This Bible Christian Society newsletter does a good job (I think) regarding the filioque clause in the creed, papal supremacy, and other matters.

Let me add my five cents:

I believe it is the current stance of the Roman Catholic Magisterium that a Roman Catholic may ask for and receive Eucharist and Penance from the hands of an Orthodox priest or bishop, IF a set of conditions is fully met. However, if they ARE met, then the Eucharist or Penance are received not only validly (we have valid apostolic succession and valid Holy Mysteries in general, as a rule) but also “LICITELY”, i.e. it is absolutely allowed and not even frowned upon for a Roman Catholic to receive the Holy Mystery (= sacrament in Catholic nomenclature).

You are right that the problem is mostly the other side of the equation, most Orthodox clergy will not offer it to the Roman Catholic in the first place. But, as Orthodoxy is NOT a centralized structure such as the RCC, mostly it holds that local eparchs are lords of their territory and borderline cases are up to their exclusive arbitration and decision. Thus, there are some (not many, but some are out there) Orthodox bishops who see a way through the rules so that a soul thirsty for Eucharist Christ or Penance may be granted that.

Same thing applies to many other matters relating to Holy Mysteries. Such as granting Holy Orders (deacons and priests). But, that is a discussion for another thread.

I send you all an Orthodox blessing, for all those who are willing to accept it:
“May St. Vasyl Czernogorec guide you to peace and friendship with his saintly patience.”

In Christ,
+Gavrilo, Bishop of Czechia
Exarchate of Vlahia, Greek Orthodox Church
Metropolitan Synod of Avlona

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