This letter has a double interest, being one of the last recorded acts of the ancient African episcopate, which was already in conflict with the Mohammedan assault, and about fifty years later was entirely swept away. It would be difficult to find stronger words than it uses to describe the Papal authority and the special gift which it recognises as belonging to the See of Peter by divine ordinance.(37) Several of the letters written by Pope Martin after the Lateran Synod testify his zeal to overthrow the Monothelite heresy. Among these is his answer to the just-quoted letter,(38) which he addresses to the Church of Carthage, and all the bishops, clergy, and laity subject to it. He praises them for the synodical letters drawn up by the Church’s glorious orator, Augustine, through the Holy Ghost, to his Apostolic See, alluding to that great confession of his(39) Primacy which we have in the letters of the Saint, and which, he says, their words repeat, and so he presents to them the acts of the Lateran Council. Particularly remarkable is the Pope’s letter(40) to the bishops under the Sees of Jerusalem and Antioch, that is, the patriarchates which had fallen under Mohammedan domination. He announces to them that, after due examination, he had condemned “the Exposition of the Emperor Heraclius, and the formula of the present serene emperor,” and he deplores the havoc which heretics had made in the East, irregularly setting up a false bishop at Antioch, the heretic Macedonius, and another, Peter, at Alexandria. The Pope adds that in his anxiety to build up the Church of God, which they were laying waste, he had, according to the power given him by the Lord in the person of blessed Peter, ordered his brother John, Bishop of Philadelphia, to supply his place in all ecclesiastical matters through the East, and to create in all cities episcopally subject to the Sees of Antioch and Jerusalem bishops, priests, and deacons, and he begs them as sons of obedience “to help our Vicar set by Apostolic authority”. The Bishop of Thessalonica, in the course of 200 years since St. Leo and the succeeding Popes had made him their Vicar for the great province of Eastern Illyricum, had become a prelate of very high rank. Paul was actually bishop, but he favoured the new heresy, and the Pope, after warning him in vain,(41) wrote deposing him, unless he received without the least omission everything which had been synodically ratified and defined at the Council. At the same time he wrote to the people of Thessalonica, enjoining them to have no society, agreement, or connection with such a man.