Should I convert to the Roman Catholic Church or the Eastern Orthodox Church?


The Petrine Office (specifically Papal Primacy, Supremacy and Infallibility) and Ecclesiology (monarchical/papal vs conciliar/patriarchal) are the foundational issue with Rome and the Orthodox… However, there are a whole HOST of issues which the Orthodox are at odds with the Catholic Church on.

First and foremost being the Filioque. As far as I can tell, the doctrine itself is no longer a serious issue… The issue is the Filioque being recited in the Creed and it being there in the first place.

The Orthodox have made it abundantly clear: so long as the Roman Church recites the Filioque, reunion is impossible. And there is no sign the Roman Church is going to drop a symbol of 1000 years of Latin patrimony… So we’re already at an impasse.

Then we have the issues of purgatory, indulgences, original sin, Immaculate Conception of Mary, unleavened bread in the Eucharist, Palamite vs scholastic theology and the associated issues of essence-energies and hesychasm, married Roman clergy / mandatory celibacy, divorce and remarriage and contraception, the nature of heaven and hell, use of icons vs statuary, fasting differences, calendar differences, issues with Latin terminology, issues with the Sacramental Character/indelible mark of Holy Orders, issues as to when the Consecration occurs (epiklesis vs words of institution), issues regarding post-VII reforms, issues regarding the Ordinary Form Roman Mass… And that’s all I can think of… Off the top of my head.

Add in the current fiasco between Constantinople, Kiev and Moscow and the fact that internal unity within Orthodoxy itself is crumbling, and you begin to see how foolish and misguidedly optimistic the notion of imminent reunion between the Orthodox and Catholic Churches truly is.


You’ve done your homework.


Spent 9 months as a Russian Orthodox catechumen half a decade ago. A week before I was sacrilegiously rebaptized, I reverted to Roman Catholicism and was convicted I was about to make a grave spiritual mistake (go into schism.)

Since that time spent another 9 months as a Roman catechumen, was Confirmed and had my marriage convalidated.

Since then have never ceased to study both Roman and Byzantine and Orthodox theology and ecumenical happenings, and regularly attend Byzantine Rite Liturgy at the local Ukrainian Catholic Church.

Over the past year have been especially involved with reaching out to the Orthodox… And it’s been a time of great pain and learning and maturing.


I’d like to hear the story. Sounds fascinating & intriguing. :sunglasses:


Up until about a year ago I used to be someone who believed reunion between the Orthodox and Catholic Churches was imminent and would take very little work.

Being in close contact with dozens of Orthodox believers including Priests and Bishops over the past year has ripped my eyes open to see how naive that notion was.

Reunion between us is at LEAST 100 years away… MAYBE.

I sincerely believe it’s possible the Orthodox and Catholic Churches will remain seperated communions until the Parousia.

I just don’t see how it’s possible that we could reunite anytime soon with so many seemingly insurmountable issues between us.

I want unity SO bad… And we don’t need to become pessimists. But we need to join pragmatism to our optimism.

The only way I could envision reunion happening this century would be a direct worldwide miraculous intervention of God himself… And I don’t see how that could be done without violating our free will. Or maybe if WWIII kicks off, and after the dust settles and the billions of bodies are buried, people realize how ridiclous our squabblings were over “Filioque” and unleavened bread and put aside their differences to embrace each other and live in unity.


Cardinal Walter Kasper, President Emeritus of the Pontifical Council for Promoting Christian Unity

Wrote in 2002

“We are increasingly conscious of the fact that an Orthodox Church does not really exist,” he contends. “At the present stage, it does not seem that Constantinople is yet capable of integrating the different autocephalous Orthodox Churches; there are doubts about its primacy of honor, especially in Moscow.” from Zenit, Kasper, 2002

I think Bp John nailed it. It’s all about the authority Jesus established, and obedience to that authority and His plan. Anything else is NOT His, and will fail.

Satan is having a ball dividing and sifting.



If we don’t stick to Peter like glue, we’ll fall apart like chaff in the wind.

We’re witnessing that firsthand in our own day in the Orthodox Churches… Division and chaos is rampant. Literally an entire country of tens of millions of Orthodox believers are considered “schismatic” by Moscow but canonical by Constantinople…


I agree. I’m neither RC or EO, but have been looking into both. I used to think before I started investigating that the EO was just like the RCC but without the Pope. However, there are several theological differences that really separate them.


I’ve heard different numbers, I’m sure you would know the exact figure, but the Russian Orthodox are the biggest Church in Orthodoxy. 60% + of Orthodoxy as I understand. Their current schism within Orthodoxy is HUGE


@ChristMYLife gave a comprehensive thorough list of differences HERE

As for Peter’s office, given to him by Jesus, this is an old issue

Satan immediately got the apostles in to an argument over the issue who is the greatest among THEM. Authority is always an issue with Satan.

Transfer this to the issues with the Catholic Church and the Orthodox

Lk 22: 24 A dispute also arose among them as to which of them was considered to be greatest μείζων 25Jesus said to them, “The kings of the Gentiles lord it over them; and those who exercise authority over them call themselves Benefactors. 26But you are not to be like that. Instead, the greatest μείζων among you should be like the youngest, and the one who rules ἡγούμενος like the one who serves. 27For who is greater, the one who is at the table or the one who serves? Is it not the one who is at the table? But I am among you as one who serves. 28You are those who have stood by me in my trials. 29And I confer on you a kingdom, just as my Father conferred one on me, 30so that you may eat and drink at my table in my kingdom and sit on thrones, judging the twelve tribes of Israel. 31“Simon, Simon, Satan has asked to sift all of you as wheat. 32But I have prayed for you, Simon, that your faith may not fail. And when you have turned back, strengthen στήρισον your brothers.”

Did Jesus confirm one of THEM is the greatest? Yes
Did the one who is greatest lobby for the position? No. He was selected by Jesus
Did Jesus confirm this one would rule over Our Lord’s kingdom? Yes
Did Jesus promise to pray especially for this one who would rule over the entire kingdom? Yes

Who is this man who is to rule and have primacy over the entire Church? The one Jesus mentions by name. Peter. Argument over.

the apostles are going to be obedient to what Jesus has established in Peter. After all, Jesus just ended their argument over this very point…

as an aside, who got them into this argument in the first place? Satan. Who is vested in keeping people sifted from this plan of Jesus? Satan. Satan is vested in keeping this argument going and never settled by endless arguing over this same point, over and over again that Jesus already settled…


Eastern Orthodoxy has about 225-250 million adherents… We’ll be generous and assume a quarter billion.

Russian Orthodoxy accounts for 150 million of that quarter billion.

The new “schismatic” Orthodox Church of Ukraine (OCU) has about 25 MILLION members… Making it the 2nd largest independent Orthodox Church behind Russia and just ahead of Romania (about 23 million).

Kiev is the historic center of Slavic Christianity, and the OCU is centered in Kiev.

The Ecumenical Patriarchate (EP) of Constantinople is the Primatial See of Orthodoxy, “first among equals,” and also has about 5 million total people under its jurisdiction.

So we’re dealing with a schism between the largest and most influential Orthodox Church, the Moscow Patriarchate (MP), and the second largest Church at the historic center of Slavic Christianity the OCU, and the Primatial and most traditionally important Orthodox Church the EP.

It doesn’t take someone with a doctorate in Orthodox theology to see the problem.

This is the worst schism the Eastern Orthodox have been involved in since the East-West schism of 1054… Nothing since is even remotely close.

IMO, the 2018 EP-MP-Kiev schism is the final, definitive proof that the Eastern Orthodox are NOT the One True Church, but are in fact a loose confederation of Byzantine Rite Catholic Churches which call themselves “the Orthodox Church” and who are in a state of separation from the larger Universal Catholic Christian Church.


Keep in mind the Eastern Orthodox state churches are now formally in schism amongst themselves:



Back in 2016 the Pan Orthodox council failed due to the Russian boycott of the meeting
1100+ yrs and they not only can’t get together, the Russians then formally go into schism. .


Note: Pope Francis sent two observers to the council: Cardinal Kurt Koch, president of the Pontifical Council for Promoting Christian Unity, and the pontifical council’s secretary, Bishop Brian Farrell. They were denied participation in the council. Instead, they were invited to opening and closing ceremonies. The Orthodox OTOH can attend an ecumenical council of the Catholic Church.


For me personally, I’ve got about 100 reasons why I believe the Catholic Church is the One Church and the Orthodox are a group of Catholic Churches separated from the rest of the Church in a state of material schism.

I’d have to literally write a book to explain every justification of the Catholic Church I’ve thought of and every argument against the Orthodox Churches.

I SERIOUSLY struggled with the battle between discerning whether the Orthodox or Catholic Church was the true Church… For years. Only in the past 6 months have I become convinced beyond any doubt what the truth of the matter is.

I’d sooner embrace martyrdom than leave the Catholic Church for the Orthodox… That’s how convinced I am. IMO, for any Catholic to defect to the Orthodox is an extremely grave mistake. Although our Churches have agreed not to proselytize each other, so it is also a mistake for Catholics to try converting Orthodox. For an individual Orthodox to simply accept the Catholic Church as orthodox is enough.

If an individual Orthodox accepts that the Catholic Church is orthodox, he could consider himself fully reconciled to the Church and in full communion with her.


I thought Bp John said it well when he wrote

(emphasis mine)

"According to the Catholic teaching, Christ did not create a church with five heads of equal importance. He established One Holy Catholic and Apostolic church whose invisible head is the Lord, but whose visible head is the Pope of Rome.

The Code of Canons of the Eastern Churches states it in these terms: “The bishop of the Church of Rome, in whom resides the office (munus) given in a special way by the Lord to Peter, first of the Apostles and to be transmitted to his successors, is head of the college of bishops, the Vicar of Christ and Pastor of the entire Church on earth; therefore in virtue of his office (munus) he enjoys supreme, full, immediate and universal ordinary power in the Church which he can always freely exercise.” (Canon 43 of the Code of Canons of the Eastern Churches)

If you don’t mind the question, What happened in those last 6 months to solidify your decision.?


Research about the failed council of Crete, research about a few other doctrinal questions, interactions with various Orthodox, and the EP-MP-Kiev schism.




Because we are Orthodox in our practice (liturgy, expression of the faith, spirituality) and Catholic because of our communion with Rome.

There are some. Especially on online forums and Facebook. However, I have plenty of Orthodox friends that respect that I call myself Orthodox in communion with Rome. We see each other as the same Church. Just an issue with upper management.

I respectfully disagree.

I know a few former Catholics, both Eastern and Roman, who have converted to the Orthodox faith, Greek and OCA, and not one had to renounce Rome. Maybe that’s just my experience.



Sounds like you’ve had much more pleasant dealings with Orthodox than me…

Granted, almost all my interactions with them since I left the ROC has been online… And I’m well aware of the issue with hyperdox fundies on the internet. So I’m biased.

And when I said “to the Orthodox you’re schismatic etc…” I should have said “to MANY Orthodox.”

I don’t think Patriarch Bartholomew himself would consider you a heretic or a true schismatic… But many under his jurisdiction would. His All Holiness has proven himself a true ally and friend to the Catholic Church… IMO the greatest friend in all of Orthodoxy. I actually consider him a living Saint.


It isn’t heretical to leave the Catholic Church for the Orthodox.

But let me make something very clear: if you’re a Catholic and understand the papacy, and you leave the Catholic Church for the Orthodox, that is the sin of schism and makes you a formal schismatic.

People born into Orthodox Churches or becoming Orthodox from atheism or Protestantism can’t be charged with the sin of schism, and thus even though they are in a state of material schism from Rome, they can’t be called schismatic because they aren’t formal schismatics.

But a Catholic who defects and separates himself from the Roman See with full knowledge in a willful manner is a formal schismatic. And formal schism is a direct sin against the body of Christ, VERY grave matter.

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