15.

 Give your understanding of the principle of the infallibility of the Church.

            The unity between God and His Church is spoken of throughout Scriptures, in which the Church is referred to as the Body of Christ (Eph 1:22-23, Rom 12, 1 Cor 10,12, Col 1); the Bride of Christ (Eph 5, Rev 21); God's Living Temple (Eph 2, 1 Peter 2); and the pillar and ground of the Truth (1 Tim 3:15). The Church is a living organism against which even the gates of hell shall not prevail (Mt 16:18), which has as its Head Christ Himself abiding with it always, even to the end of the age (Mt 28:20).

            It is from this unity with God that the Church as a whole cannot err. The Church cannot submit to false teaching, and it cannot allow any admixture of falsehood. An error of the whole Church would be tantamount to its spiritual death, yet, according to Christ's promise, the Church cannot die. As Protopriest Victor Potapov explains:

If the Orthodox Church as a whole cannot err, her individual members, individual gatherings and groups, and even large parts of her can fall into error. And since the opinion of the whole Church is manifested at Ecumenical Councils, the Ecumenical Councils are the infallible custodians and interpreters of divine revelation — not because the members of the Councils are individually infallible, but because the decisions of the Councils are the voice of the whole Church, which is directed by the grace of the Holy Spirit (the decisions of the Councils always begin with the words: “It seemed good to the Holy Spirit and to us”) [Orthodoxy and Heterodoxy].

Additional pertinent information regarding the infallibility of the Church is provided by Fr. John Whiteford:

Not only must we seek that which is universal and ancient, we must further hold to those teachings which represent the consensus of the Fathers, rather than the isolated views of a given Father or teacher. This is what is meant by consent, or the faith believed by all. Infallibility resides in no individual in the Church save Christ alone, and so there are examples of Fathers who, while generally teaching the faith accurately, at times taught things which were in error. The difference between these Fathers and the heretics is that the Fathers taught these things in innocence, while heretics teach heresy in opposition to the Church and despite attempts at correction. Even St. Paul erred, but was corrected by St. Paul (see Gal 2). Twice in Revelation, St. John tells how he worshiped an angel, then was corrected by that angel! [Sola Scriptura: an Orthodox Analysis of the Cornerstone of Reformation Theology, p. 42; emphasis added].