The See of Peter

The Early Church and Peter's Primacy

Letter XXVI, from Flavian to Pope Leo

Synopsis: Flavian writes to Leo — in response to Leo’s letter of inquiry — to provide a full account of Eutyches’s heresy, his deposition at the Constantinople synod, and his subsequent campaign of disruption; to inform Leo that Eutyches lied in claiming he submitted an appeal during the proceedings; and to appeal to Leo to confirm the canonical deposition, strengthen the emperor’s faith, and act with the customary confidence of his priesthood, since the matter needs only the impulse and support of Leo’s action, and his sacred letters will end the heresy and prevent any further synodal disturbance.

Flavian, bishop of Constantinople, to the most holy and most blessed father and fellow minister, Leo, greetings in the Lord.

Nothing is more precious to priests, as Your Holiness knows, than piety and the right distribution of the word of truth. All our hope, our salvation, and the reward of the promised goods depend on this. We must therefore do all things and undertake every labor to preserve the true faith and the expositions and dogmas of the holy Fathers, ensuring they remain whole and inviolate in all circumstances.

Chapter I: Eutyches’s Heresy, His Condemnation, and His Subsequent Conduct

Seeing the orthodox faith harmed and the heresies of Apollinaris and Valentinus revived by the impious monk Eutyches, we judged it necessary not to overlook but to expose his error publicly, for the caution of the people. Concealing the disease of his perverse sect, Eutyches shamelessly presumed to spread his impiety to many, attacking our gentleness, and asserting that before the Incarnation of our Savior Jesus Christ there were two natures — divinity and humanity — but that after their union only one nature remained; ignorant of what he says or asserts.

As Your Holiness’s piety knows, the union of the two natures in Christ does not confuse their properties; both natures preserve their properties intact in the union. Yet Eutyches added a further impiety, saying that the body of the Lord taken from Mary is not of our substance or human material — calling it human but denying that it is consubstantial with us or with her who bore Him according to the flesh.

The acts of the holy and ecumenical Council of Ephesus, in the letter written to the condemned Nestorius, state plainly: The diverse natures that came together in true unity form one Christ and Son, not abolishing their distinction by the union, but divinity and humanity together perfecting one Lord Jesus Christ through an ineffable and incomprehensible union. Your Holiness, having read these acts, knows this. Disregarding them, Eutyches imagines he will escape the penalties that council prescribed.

Since many of the simpler faithful had their faith harmed by his disputations, the most reverend bishop Eusebius brought an accusation against him. Brought before the holy synod and declaring his views, we deposed him as alien to the true faith — as the acts transmitted with this letter to Your Holiness will attest.

It is fitting, I believe, to inform you that Eutyches, justly and canonically deposed, did not seek to correct his prior errors through repentance and tears, to appease God and soothe our heart in its grief over his fall. Instead, he strove to disturb this most holy church — publicly posting libelous and slanderous writings, and presenting insolent petitions to our most pious and most Christian-loving emperor — attempting to trample the divine canons underfoot.

Chapter II: Eutyches Lied About Submitting an Appeal; Leo’s Letters Are the Decisive Remedy

After all of this, We received the letters of Your Holiness, delivered through the admirable count Pansophius, informing us that Eutyches had sent deceitful libels to you, claiming that during his trial he had submitted appeals to us and to the bishops of the synod and had appealed to Your Holiness. This he never did — lying as the father of lies, imagining he could steal into Your Holy ears through deceit.

Moved, most holy father, by all that he has dared and by what has been done against us and against this most holy church, act with the customary confidence that befits Your Priesthood. Vindicating the common order and cause of the holy churches, deign through your letters to confirm the canonical deposition made against him, and to strengthen the faith of our most pious and most Christian emperor. The matter needs only the impulse and support of Your action, through which — through Your Prudence — all things will at once be restored to health and peace. For thus the heresy that has arisen, and the tumult excited by it, will easily cease, with God’s cooperation, through Your sacred letters; and the proposed synod being rumored will be prevented, lest the most holy churches of the whole world be disturbed. I and those with me salute all the brotherhood with you. May you remain safe in the Lord, praying for us, most God-loving and holy father.

Source/Reference

PL 54:743

Notes / Historical Commentary

Letter XXVI is Flavian’s second letter to Leo — his full response to Leo’s letter of inquiry (Letter XXIII), delivered in late February or March 449. Where Letter XXII had been a relatively brief notification of the condemnation, Letter XXVI is a comprehensive account: the theological errors Eutyches taught, the proceedings of the synod, Eutyches’s subsequent conduct, and the explicit refutation of Eutyches’s claim that he had submitted an appeal during the trial. It is also, in its closing paragraphs, one of the most direct appeals to Roman authority anywhere in the correspondence — coming from the Patriarch of Constantinople himself.

The closing of Chapter II is the letter’s most significant passage. Flavian asks Leo to do three things: confirm the canonical deposition, strengthen the emperor’s faith, and act with the confidence of his priesthood. The ground on which Flavian makes this request is not a canonical rule or a conciliar grant — it is the established pattern of what Leo’s authority accomplishes. The matter needs only “the impulse and support of Your action,” and Leo’s sacred letters will end the heresy. This is the same structure of authority visible in Letter XXII, but stated even more directly: the patriarch of Constantinople is telling the bishop of Rome that his letters are the decisive instrument by which a major Eastern controversy will be resolved. The Apostolic See does not need to convene a new synod; it needs to act, and when it acts the heresy will cease.

The reader should note the specific request: Flavian asks Leo to *confirm* the canonical deposition, not to retry or review it. The condemnation has already been made; what it lacks is the backing of the Apostolic See. This is the same pattern Leo himself had articulated in Letter XXIII — the Apostolic See needs to be informed, and its judgment gives the proceeding its full standing. Flavian understood the same logic from his end. A local synodal condemnation, however well-grounded, required Roman confirmation to carry universal force. That is not Flavian’s invention or Leo’s demand; it is simply how the structure of authority was understood to work by both the Roman and the Constantinopolitan bishops at the height of the Eutychian controversy.

There is a second, older version of this letter preserved in a Spanish canonical collection, also included in the PL at columns 749ff. As with Letter XXII, the two versions are substantially equivalent in content and theological substance, with differences primarily in Latin phrasing. The translation here follows the main bilingual version at columns 743–748, which is the version preserved in the principal conciliar collections.