Catholicism and Ecumenism

Pope Leo XIV greets Orthodox Metropolitan Emmanuel of Chalcedon, a bishop of the Orthodox Ecumenical Patriarchate, during a meeting in the Apostolic Palace at the Vatican June 7, 2025, with participants attending a conference on the ecumenical implications of the 1,700th anniversary of the Council of Nicaea.  (Photo by Vatican Media)

Introductory Comments

The Catholic faith is one of the most known but least understood of various faiths, not just among people of other religions but also among other Christians. Besides the fact of the mysteries surrounding the mystical aura of the 2000 year-old Church institution, this lack of understanding is in part because of the intricacies of its faith system which cannot be understood in simplistic monotonal terms. When people confront this system with simplistic mindsets without first truly understanding the vast minute intricacies underlying each Catholic truth claim, some tend to become hostile to the Church because of such lack of understanding or ignorance.

And so it is with the prevalent ignorance of many other Christians on the Catholic Church’s understanding of ecumenism. When questions like “Why does the Catholic Church not permit other Christians to receive the Eucharist when we are all supposed to be part of the same Body of Christ” or “Why does the Catholic Church not apply the term ‘church’ for us?” are asked, they betray a lack of understanding of what the Catholic understanding may be on such issues.

Of course, agreeability is not a requisite in ecumenical efforts; but the pursuit of understanding is. Therefore, it is not the aim of this writing to solicit agreement, but rather to clarify underlying assumptions and theological presuppositions as we all embark on ecumenical efforts in the service of truth.

Many non-Catholics Christians tend to impose their assumptions on the Catholic Church by telling us how ecumenism should be exercised (for example, insisting that we should practise open communion at the celebration of the Eucharist), and even going so far to try telling us what we believe based on their own misconceptions about Catholicism (for example, that the Catholic Church’s claim of commitment to ecumenical efforts is “dubious and smutty”).

Contrary to such ignorant accusations, Catholicism has over the years developed what has probably become the most substantive system of understanding ecumenism among the various Christian traditions. Therefore, in these next couple of days, I will be posting up a series on the Catholic Church’s position on ecumenism.

This treatise will not be exhaustive (because any discussion on ecumenism would necessitate a thorough investigation into the Catholic dogma of the Church), but it will be adequate to provide an understanding to people who truly wish to begin their journey of deeper understanding. And yet, this treatise would indeed be found sorely lacking for people who desire to antagonise and interrogate. Hence, I post this series for the former and not the latter.

What Ecumenism Is Not

Before the Catholic conception of ecumenism is expounded, it is first and foremost crucial to clarify some points in the negative, i.e. what ecumenism is not.

Firstly, ecumenism is not yet achieved.

First and foremost, it must be known to the dialogue partners of the Catholic Church that ecumenism is not something that has already been achieved, in our understanding. Ecumenism is a desired future, a goal, because it is the desire of the Son of God who prayed “that [we] may be one”. But this does not in itself mean that we are already one, even though we all profess faith in Him.

Ecumenism is not yet achieved because, unlike the conception of some factions of Christians, ecumenism is not merely an attitude or state of mind which says “Let us just behave like we are one, and we will be one”. Ecumenism, in the assessment of the Catholic Church, is much, much deeper than that, and she refuses to take a superficial stance on the matter.

Secondly, ecumenism is not easily achievable.

It needs to be made known that the Catholic Church does not think that ecumenism is something easily achievable. In fact, from a human viewpoint, it is not even remotely achievable, especially with our Protestant brothers and sisters. To return to a state of unity with over 40 thousand denominations globally, each with its own distinct doctrinal claims, is not a human possibility. This is true even without taking account of the fact that even within any one particular denomination, its individual members (i.e. both clergy and laity) hold differing theological viewpoints on crucial matters.

Of course, many would then say that we should focus our ecumenical efforts on a spiritual unity rather than a theological unity. This will not do for the Catholic Church; neither will it do for the Orthodox Churches, for that matter (although I will not assume the audacity of right to speak on behalf of that well-respected tradition in this series). This proposed alternative would sorely compromise our understanding of revelation and truth.

Well, ecumenism is indeed a possibility; just not a human one. Therefore, while we seek unity, prayer is the ultimate embodiment of that desire, because only God can unite His own fragmented Body. And as we pray, we also dialogue prayerfully with others by gentle invitation.

Thirdly, ecumenism is not false union.

Pope Benedict XVI and the Archbishop of Canterbury at Westminster Abbey, Friday, 17 September 2010

The Catholic Church does not see that the endeavour towards ecumenism necessitates the putting aside of all our theological differences.  Pretending that there are no differences and relating to one another as a “united body” by resting on the lowest common denominator of the faith is to pander to false and promiscuous union. True ecumenism, by the standards of the Catholic Church, is to be measured in terms of consistency with our Creed (the faith and moral claims of the Church), Code (the discipline of the Church) and Cult (the liturgical worship of the Church).

So why do we not practise, say, open communion at the celebration of the Eucharist? Because for the Catholic Church, the sharing in one bread is not a means to unity, but rather, a sign of a unity (of Creed, Code and Cult) that should have already taken place prior to the sharing in one bread. We understand that our Protestant brethren do not agree with this, but the Catholic Church expects that her standards be respected within the context of her own liturgical celebration. It is, after all, our liturgy. Similarly, the Orthodox Churches generally do not permit for our Catholic communicants to receive their Holy Eucharist in their liturgies even though the Catholic law permits for them to do so where they cannot find a Catholic Church in which to worship. The Catholic Church teaches its children to abide by the disciplines of the Orthodox Churches even if it means the sad reality of being “deprived” of participation in the Holy Eucharist. No big fuss is made about such. That much respect the Catholic Church accords to the preferences of other communities, and that much respect it expects from others in her own ecclesial practices in accordance with her theological beliefs.

Unity is indeed important to the Catholic Church, and it remains her priority to strive towards that. However, it is a unity in the service of truth that she seeks, not just a unity for the sake of itself. For this reason, the Catholic Church does not - she cannot - sacrifice truth at the altar of unity. In the understanding of the Catholic Church, when an authentic unity has been reached, it is a unity of truth. Therefore, two conflicting truths (e.g. the Eucharist being the body, blood, soul and divinity of Christ for some and being a mere symbol for others) can neither be a source of nor a means to unity. Whilst the Catholic Church respects that this inconsistency does not perturb the Protestant practice of inter- and open-communion despite the presence of over 300 different interpretations on the Eucharist among the over 40 thousand denominations, she herself cannot pander to it.

Ignorant denominational pluralists are frequently scandalised by the fact that the Catholic Church refuses to take such a pluralistic position on ecumenism. The position of the Catholic Church is always inclusive but not pluralistic. The principle of inclusion enables the Church to make space for others and to recognise the good in others without having to compromise our self-understanding. It also respects the self-understanding of others, keeping in mind that respect does not mean consent or agreement. Unity based on a whitewashing of differences, according to Pope Benedict VI, is a facade and only stalls fruitful dialogue.

Furthermore, the pluralistic position is often not as generous as it claims itself to be, because it actually excludes those who refuse its position. In other words, to the pluralist, everyone must acknowledge that all Christian communities are on par with one another. Those who refuse to acknowledge that are automatically excluded; this irony is often a blind spot to the pluralists who are quick to exclude those who disagree with their enterprise of levelling down all Christian traditions. Denominational pluralism, often justified in the name of “ecumenism”, is therefore a logical fallacy. The inclusive position, on the other hand, respects one’s self-identity and the self-identity of others: all are not necessarily seen as equal or agreeable, but all are respected.

What Ecumenism Is

Having elaborated what ecumenism is not, from the Catholic perspective, it is also important to define what it is. In order that dialogue may be open and respectful, this definition must be given in utter honesty and without a hidden agenda born out of the fear to offend. The Catholic Church speaks respectfully with distinct honesty and expects her partners to do the same; this is a basic requisite for healthy dialogue.

Ecumenism, as far as the Roman Catholic Church is to be a visible unity. In other words, for her, the goal of ecumenism is union with the Catholic Church.

The Catholic Church does not demand union, but it hopes to arrive at it through mutually respectful dialogue. And even if this union was not possible, the Catholic Church would continue striving in dialogue so that she may honour the desire of her Lord for His disciples to eventually be one.

The Catholic Church makes no apologies for being so forthcoming about its agenda and its understanding of ecumenism. Again, it must be emphasised, she believes that honesty is a requisite of fruitful dialogue, and would therefore rejoice in the respectful honesty of all other Christian communities in laying out their self-understanding. So it really is about laying out our cards in the open, with utter honesty and yet respect, and then proceeding with dialogue from there. It is fundamental to any kind of dialogue that the participants are clear about their own identity. Dialogue cannot be an occasion to accommodate or soften what you actually understand yourself to be.

The Pope, along with all Christians, believes salvation comes from belief in and acceptance of Jesus Christ as one’s personal Lord and Saviour, as the only mediator between God and man.  The Bible says as much.  But he also affirms the long-standing doctrine of the Catholic Church that Jesus chose to work out this plan of salvation through His Church under the direction of His twelve apostles and their successors (bishops in communion with the Pope).

The Catholic Church does not see the unapologetic expression of theological differences as a barrier to friendship, respect and brotherhood.  In fact, a false sense of tolerance has made it now almost impossible to say, “I think I’m right,” without being called a bigot by denominational pluralists.  Neither the Pope nor the entire Catholic Church would/should stand for that.

Our Understanding of Other Christians

The Catholic Church does not take a simplistic view of other Christian communities. Her understanding of the various communities is well-nuanced and therefore does not lump them all together.

The Orthodox Churches are seen as “true churches”.

Pope Leo XIV sits next to Cardinal Kurt Koch, prefect of the Dicastery for Promoting Christian Unity, as he poses for a photo with participants attending a conference on the ecumenical implications of the 1,700th anniversary of the Council of Nicaea in the Clementine Hall at the Vatican June 7. (CNS photo/Vatican Media)

The Catholic Church recognises the Orthodox churches as true churches; in fact, they are frequently called “sister” churches. These churches born in the East, although not in communion with the Bishop of Rome, are distinctly characterised by apostolic succession and therefore have valid sacraments.

We do estimate that such churches are suffering from a “wound” since they do not recognise the primacy of the Bishop of Rome, the Pope, among other Patriarchs. However, the wound is not so severe that it has caused them to lose the gravity of the marks of a true Church: oneness, holiness, catholicity and apostolicity. They still contain sufficient marks to constitute true churches.

[Note: Of course, there are some Eastern Churches who have throughout the centuries returned to full communion with the Bishop of Rome and have come to be called “Eastern Catholic Churches”. These are not wounded and continue to exercise their ecclesial life based on the distinctives of their traditions in consistency with the deposit of faith and in full communion with the Pope. There are also about two Eastern Churches which have never broken communion with Rome before in the course of their history.]

Protestant communities are called “ecclesial communities”.

Luther hammers his 95 theses to the door Ferdinand Pauwels (1830–1904)

Whilst there is a measure of woundedness in the Eastern Churches, it said that the “wound is still more profound” in the Protestant denominations. The wound is so profound that these communities do not sufficiently possess enough marks of a church to be properly called “churches”. Therefore, the Catholic Church calls these communities “ecclesial communities originating from the Reformation”, a term used to refer to Protestants and Anglicans (the latter often do not identify themselves as “Protestants”, therefore it is right to identify them separately with due respect to their self-identity). A document of the Catholic Church says, “Despite the fact that this teaching has created no little distress... it is nevertheless difficult to see how the title of 'Church' could possibly be attributed to them”.

The Catholic Church does not mean these terms to be derogatory; rather, they are meant to be honest terms. She would expect no less from her dialogue partners. In the same way, there are well-meaning Protestant segments who call the Catholic Church “the Harlot of Babylon” and the Pope “the antichrist”. The Catholic Church does not react even to such derogatory name-calling, perhaps by way of respecting the rights of such well-meaning Christians to determine what they truly believe and to be honest about it. A Pentecostal theologian once said in a dialogue with the Catholic Church, “We think you Catholics are not saved, and our aim is to save you!” The point was well-received because the open honesty was respected.

But at the same time, the Catholic Church continues to recognise that within these ecclesial communities is to be found elements of truth and sanctification which assist people in the salvific process. The Catholic Church also continues to acknowledge, admire and deeply respect those who continue to proclaim Christ in local and foreign lands, the evangelists and those who die because of their faith.

And yet, whilst the Second Vatican Council's opening to other faiths recognised that there were “many elements of sanctification and truth” in other Christian denominations, the Church stresses that only Catholicism has all the elements to be Christ's Church fully.

It is possible, according to Catholic doctrine, to affirm correctly that the Church of Christ is present and operative in the churches and ecclesial communities not yet fully in communion with the Catholic Church, on account of the elements of sanctification and truth that are present in them […] In fact the Spirit of Christ has not refrained from using them (other Christian denominations) as instruments of salvation, whose value derives from that fullness of grace and of truth which has been entrusted to the Catholic Church.

Responses to Some Questions Regarding Certain Aspects of the Doctrine of the Church

Recognising also that the Protestant Reformation took place in waves, and that each wave of the Reformation represented a further drift away from the fullness of the deposit of faith, the Catholic Church further categorises the ecclesial communities into three separate clusters. The first batch of communities arising from the Reformation is known as the “Reformation communities” (i.e. Reformed, Anglican, Presbyterian, Lutheran). The second batch, most often further breakaways from the Reformation communities themselves, are termed “free communities” (i.e. Methodists, Baptists, Quakers). Finally, the subsequent communities arising from further breakaways are categorised under “sects” (i.e. Brethren, Salvation Army, Pentecostal denominations, Seventh Day Adventists, etc).

The Catholic Church and Ecumenism Today

The Roman Catholic Church has always considered it a duty of the highest rank to seek full unity with estranged communions of fellow Christians, and at the same time to reject any promiscuous and false union that would mean being unfaithful to or glossing over the teaching of Sacred Scripture and Sacred Tradition.

Over the recent past, there has been a change in emphasis of the Catholic perspective on ecumenism.  Before the Second Vatican Council (1962-1965), the main stress was laid on this second aspect, i.e., avoiding the possibility of compromising the teaching of Scripture and Tradition.

For example, Canon 1258 of the 1917 Code of Canon Law says: “It is illicit for the faithful to assist at or participate in any way in non-Catholic religious functions.  For a serious reason requiring, in case of doubt, the Bishop's approval, passive or merely material presence at non-Catholic funerals, weddings and similar occasions because of holding a civil office or as a courtesy can be tolerated, provided there is no danger of perversion or scandal”.

The most recent 1983 Code of Canon Law, however, whilst absolutely forbidding Catholic priests to concelebrate the Eucharist with members of communities not in full communion with the Catholic Church (Canon 908), allows, in certain circumstances and under certain conditions, other sharing in the sacraments.  Furthermore, the Directory for the Application of Principles and Norms on Ecumenism, 102, states, "Christians may be encouraged to share in spiritual activities and resources, i.e., to share that spiritual heritage they have in common in a manner and to a degree appropriate to their present divided state."

Pope John XXIII (Photo by Fotografia Felici, Wikimedia Commons)

Pope John XXIII, who called together the Council that consequently brought about this change of emphasis, said that the Council's aim was to seek renewal of the Church itself, which would serve, for those separated from the See of Rome, as a "gentle invitation to seek and find that unity for which Jesus Christ prayed so ardently to his heavenly Father”.

Ecumenical endeavours continue to remain a priority of the Roman Catholic Church today. But what the Catholic Church construes as an ecumenical endeavour should not be misunderstood by other Christians who insist on their own brand of ecumenism.  The Catholic Church respects that these have their own rendition of ecumenism, whilst she works out of her own ecumenical endeavours in ways consistent with her Sacred Tradition and ecclesial life.

The Holy Father, Pope Benedict XVI, has issued an unmistakable call to the Body of Christ, emphatically instructing the Church that “ecumenism is not an option but a sacred duty”.