Rome maintains that every Ecumenical Council has been approved by the Pope and that each has had papal representation. In actuality, the early councils were called by the emperor and it is only retrospectively that papal approval was given. Although it has been presumed that councils were ecumenical, that is to say, they represented the whole church, in actuality, some councils have been regional. The western bishops went to Aquileia in 381. The Orthodox churches recognize the importance of ecumenical councils, a principle that was evoked at the first ecumenical council in its fifth canon, and which is reiterated in the nineteenth canon of the Council of Chalcedon.
Ecumenical councils derive their status by the way in which they are accepted by the whole church.
They are infallible, according to the Orthodox Church, because the Church is infallible. This does not mean that the Church does not err as an institution, but that, as the Body of Christ the Church, can never be faithless to the mission which was entrusted to it by its Head, Jesus Christ. The Councils speak for the Church because they are made up of the bishops who are the descendents of the original apostles and who, when gathered together, represent the authority of Christ and the discernment of the Holy Spirit.