"And, to say so once for all, we decree that the faith shall stand firm and remain unsullied until the end of the world as well as the writings divinely handed down and the teachings of all those who have beautified and adorned the Church of God and were lights in the world, having embraced the word of life. And we reject and anathematize those whom they rejected and anathematized, as being enemies of the truth, and as insane ragers against God, and as lifters up of iniquity."
"But if any one at all shall not observe and embrace the aforesaid pious decrees, and teach and preach in accordance therewith, but shall attempt to set himself in opposition thereto, let him be anathema, according to the decree already promulgated by the approved holy and blessed Fathers, and let him be cast out and stricken off as alien from the number of Christians. For our decrees add nothing to the things previously defined, nor do they take anything away, nor have we any such power." (conclusion of the first Canon of the Council in Trullo – "Quinisext" [692 A.D.])The ”Fathers” referenced were the leaders and confessors of the Orthodox Faith of the first Six Ecumenical Councils, as follows:
- First Council at Nicea (325) – 318 fathers combatting the heresy of Arius, declaring the consubstantiality and co-equal worship of “the Three Persons comprehended in the Divine Nature” (Father, Son, and Holy Spirit);
- Second Council at Constantinople (381) – 150 fathers asserting the divinity of the Holy Spirit contrary to the heresy of Macedonius, and that the Person of the God-man, Jesus Christ, had a human mind against the false teaching of Apollinaris. The final section of the Nicene Creed, after “And in the Holy Spirit,” was appended.
- Third Council at Ephesus (431) – 200 fathers condemning the heresy of Nestorius who taught the divine and human natures of Christ had contact but were divided from each other, confessing the truth that the incarnate Son of God is one by glorifying the Virgin Mary as Theotokos, that is, Birthgiver-of-God;
- Fourth Council at Chalcedon (451) – 630 fathers decreeing that “the one Christ, the Son of God, is of two natures, and must be glorified in these two natures,” the two natures united in the one Person of the God-man “without confusion, without change, without division, without separation.” The leading heresy condemned was that of Eutyches who emphasized the one divine nature of Christ at the expense of the human (Monophysitism [Gk. mono-physis, “one-nature”];
- Fifth Council at Constantinople (553) – 165 fathers reaffirming the doctrinal definition of the Fourth Council, and condemning the universalist errors of Origen;
- Sixth Council at Constantinople (680/1) – beginning with 43 and ending with 174 fathers, professing that the incarnate Son of God possesses “two natural wills or volitions and two natural operations” (or, energies), condemning the subtler forms of Monophysitism known as Monoenergism (Gk., mono-energeia, "one-energy/operation") and Monotheletism (Gk., mono-thelesis, “one-will”).
In addition to doctrinal decrees, the Fathers of each Council composed disciplinary Canons. These Canons (Gk., kanon) are standards of Christian administration and behavior in three broad categories: range of influence and duties of Clergy, especially bishops; conduct of services and common life within the Church; and health of the soul in moral correction.
These Canons are best understood as rulers, or yardsticks, defining boundaries and limits of what is healthy for life and growth in the Faith, not as rules to be enforced legalistically. Just as with the Definitions of the Faith passed on from the Fathers, these Canons are binding in the Church today as we continue to apply the unchangeable truths of the Faith in our generation.