Ecumenical Councils: What makes them "Ecumenical"?

I’m at a loss as to where I ought to put this, so if I’ve misidentified the correct subforum I apologize and hope that a moderator will graciously move it to its appropriate venue.

The Catholic and Orthodox churches have had councils and synods throughout their histories yet both churches recognize select few as “Ecumenical”, insofar as their dogmatic decrees are binding on the faithful of the Universal Church. I’m curious as to which qualities are necessary in a council/synod for it to be understood as “Ecumenical” in the Catholic Church (if you also have insight into the Orthodox Church I’d appreciate that as well). I understand that the benchmark for “ecumenicity” today may be very different than what it was in the fledgling Church, so the historical evolution of what makes a council ecumenical would also be quite helpful.

In particular, I’m curious if:

  • any and all councils that the Pope ratifies is by default considered ecumenical (in which case I would assume that the upcoming Synod on the Family must then be “Ecumenical”),
  • is the Pope’s ratification of a synod/council necessary but not sufficient for “ecumenicity”,
  • does there exist a quorum of bishops necessary for an Ecumenical Council (whether the Pope ratifies it or not),
  • are there any good Rules of Thumb for quickly assessing the “ecumenicity” of a council,
  • can (or has) the Church retroactively rebuked a previous Ecumenical Council as not having been truly ecumenical (***AND IF SO, WHY?***).

Thanks all for your help. :slight_smile:

Modern Catholic Dictionary:

COUNCILS OF THE CHURCH. Authorized gatherings of bishops for the purpose of discussing ecclesiastical problems with a view to passing decrees on matters under discussion. In Roman Catholic terminology, if all the bishops are called to participate and actually represent the Christian world, the assembly is called ecumenical, which means universal; if only part of the hierarchy is invited, the council is particular. The latter may be plenary or provincial, depending on whether a single provincial area, e.g., the dioceses of Ohio, or a whole country sponsors the gathering. Church councils, even on a provincial basis, enjoy juridical authority in religious questions that is distinct from the legislative powers of individual bishops. In this respect also, councils differ from episcopal conferences, which are not, as such, legislative assemblies.

Canon Law:


Can. 336 The head of the College of Bishops is the Supreme Pontiff, and its members are the Bishops by virtue of their sacramental consecration and hierarchical communion with the head of the College and its members. This College of Bishops, in which the apostolic body abides in an unbroken manner, is, in union with its head and never without this head, also the subject of supreme and full power over the universal Church.

Can. 337 §1 The College of Bishops exercises its power over the universal Church in solemn form in an Ecumenical Council.

§2 It exercises this same power by the united action of the Bishops dispersed throughout the world, when this action is as such proclaimed or freely accepted by the Roman Pontiff, so that it becomes a truly collegial act.

§3 It belongs to the Roman Pontiff to select and promote, according to the needs of the Church, ways in which the College of Bishops can exercise its office in respect of the universal Church in a collegial manner.

Can. 338 §1 It is the prerogative of the Roman Pontiff alone to summon an Ecumenical Council, to preside over it personally or through others, to transfer, suspend or dissolve the Council, and to approve its decrees.

§2 It is also the prerogative of the Roman Pontiff to determine the matters to be dealt with in the Council, and to establish the order to be observed. The Fathers of the Council may add other matters to those proposed by the Roman Pontiff, but these must be approved by the Roman Pontiff .

Can. 339 §1 All Bishops, but only Bishops who are members of the College of Bishops, have the right and the obligation to be present at an Ecumenical Council with a deliberative vote.

§2 Some others besides, who do not have the episcopal dignity, can be summoned to an Ecumenical Council by the supreme authority in the Church, to whom it belongs to determine what part they take in the Council.

Can. 340 If the Apostolic See should become vacant during the celebration of the Council, it is by virtue of the law itself suspended until the new Supreme Pontiff either orders it to continue or dissolves it.

Can. 341 §1 The decrees of an Ecumenical Council do not oblige unless they are approved by the Roman Pontiff as well as by the Fathers of the Council, confirmed by the Roman Pontiff and promulgated by his direction.

§2 If they are to have binding force, the same confirmation and promulgation is required for decrees which the College of Bishops issues by truly collegial actions in another manner introduced or freely accepted by the Roman Pontiff.

I have heard a couple different approaches on this.

Some say that any council attended and accepted by all the Orthodox Churches in communion with each other constitutes an ecumenical council, such as the one being planned for 2-3 years from now.

Others feel there cannot be an ecumenical council without the 5 “original” sees being represented. Therefore, since Rome is in schism, there can be no ecumenical council until that issue is resolved.

I think it’s the latter approach that is being put forth by a Russian Orthodox spokesman in the quote below, although he may simply be suggesting a chronological deadline, that after 787 there can be no more ecumenical councils - which would be still a third approach.

When asked whether the forthcoming council is ecumenical, Legoyda said: “The council, the preparation of which is entering its final phase, is called the Holy and Great, sometimes Pan-Orthodox. Calling it ecumenical is not accepted and is incorrect. The last ecumenical council was convened in Nicaea in 787, and since then such councils have not convened."

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