The 165 Fathers of the Fifth Ecumenical Council

The Holy 165 Fathers of the Fifth Ecumenical Council are the bishops who gathered in Constantinople in 553 at the order of Emperor Justinian to defend the faith in Christ confessed at the Council of Chalcedon. The Church commemorates them on 25 July.

The trouble had begun years earlier. In 535 the see of Constantinople was held by Anthimus of Trebizond, who held the Monophysite teaching. Pope Agapetus of Rome, then in the capital, had him removed, and the priest Menas, commemorated on 25 August, was consecrated in his place. The Monophysite leaders, among them Severus of Antioch and Peter of Apamea, were condemned, but the Church remained deeply divided. At the same time the teachings of Origen were spreading through the monasteries.

Justinian believed he could bring peace by condemning three groups of writings, known as the Three Chapters, which the Monophysites regarded as Nestorian: the person and writings of Theodore of Mopsuestia, the writings of Theodoret of Cyrrhus against Saint Cyril of Alexandria, and the letter of Ibas of Edessa to Maris the Persian.

The council opened on 5 May 553 in Constantinople under the presidency of Patriarch Eutychius of Constantinople. Pope Vigilius was in the city but did not attend the sessions; he later accepted the council's decisions. The Fathers confessed the faith of the four previous Ecumenical Councils and condemned the Three Chapters. In their anathemas they set out that in Christ the two natures are united in a single hypostasis, that of the Word of God, that One of the Holy Trinity was crucified in the flesh, and that the Virgin Mary is truly the Mother of God. Among the heretics of the past they also named Origen.

The Fifth Council issued no canons. Its legislative work, together with that of the Sixth Council, was completed by the Quinisext Council, also held in Constantinople, in 691-692.

The number 165 is that of the bishops who signed the council's decisions. Their names are not listed one by one in the calendar; the Church honours them together as those who guarded the right faith concerning Christ.