|The deposition of Saint Flavian from Shea's The Pictorial Life of the Saints.|
How Flavian was killed is not precisely clear. Here is an account of what happened drawn from the Ecclesiastical History of Evagrius, written not long after the event, as part of Evagrius's explanation of why the Council of Chalcedon was called:
The Ecclesiastical History of Evagrius, Book II, Chapter II).In most accounts modern accounts of this event, Flavian is said to have been gravely injured by this rough handling and perished a few days afterwards. Blame for his death was affixed by many to Dioscorus and Barsaumas, as we can see more clearly in a dramatic scene recorded in the Acts of the Council of Chalcedon shortly after AD 451:
Diogenes the most devout bishop of Cyzicus said: ‘Barsaumas, who entered among them, slaughtered the blessed Flavian. He was standing there and saying, “Slaughter him.” Since he is not in the petition, why has he come in?’
All the most devout bishops exclaimed: ‘Barsaumas destroyed all Syria. He incited thousands of monks against us.’
The most magnificent and glorious officials said to the monks: ‘In accordance with your request in the petition, our most divine and pious master gave orders both that the holy council should convene and that you should now gain entrance. So now that you have entered, have the patience to learn the decisions of the same most holy council concerning the faith.’
Carosus and Dorotheus the most devout archimandrites and the other monks said: ‘We ask that the plaint we have brought be read out.’
The most devout bishops exclaimed: ‘Drive out the murderer Barsaumas. The murderer to the stadium! Anathema to Barsaumas! [Send] Barsaumas into exile!’Saint Flavian's name would be forever immortalized, however, by the Tome of Leo which was written before his death. Addressed to Flavian by Pope Leo, this work was a condemnation of Eutyches, a staunch defense of Flavian's position, as well as an act of faith that would become a doctrinal statement on the two natures of Christ, human and divine.