Schism of the Three Chapters

The Schism of the Three Chapters was a schism that affected the Orthodox Catholic Church in North Italy lasting from 553 to 698 AD, although the area out of communion with Rome contracted throughout that time. It was part of a larger Three-Chapter Controversy that affected the whole of Roman-Byzantine Christianity.

The Three-Chapter Controversy came out of an attempt to reconcile the Non-Chalcedonian (Monophysite) Christians of the Middle East with the Chalcedonian Church. A major part of the attempted compromise was a condemnation of certain works of Eastern Christian writers such as Theodoret of Cyrus and Theodore of Mopsuestia soon became known as the Three Chapters. These were seen to be particularly objectionable by the opponents of the Council of Chalcedon and in an attempt to win them to the Council the condemnation was seen as a way of reassuring them.

The condemnation took place as an Imperial Edict around 543, accompanied by the Tome of Pope Leo I that had been read at the Council of Chalcedon nearly one hundred years before. There was some resistance in the Greek speaking, eastern part of the Church, although in the end the leading Eastern bishops did agree to condemn it. Those who would not condemn these works were accused of being sympathetic to the heresy of Nestorianism.

In 553 by council, the bishops of Aquileia, Liguria, Aemilia, Milan and of the Istrian peninsula all refused to condemn the Three Chapters, arguing that to do so would be to betray Chalcedon. They broke off communion with Rome, under the leadership of Macedonius of Aquileia (535-556).

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