The See of Peter

The Early Church and Peter's Primacy

Letter XXXIV, from Pope Leo to Bishop Julian of Cos

Synopsis: Leo writes briefly to Julian of Cos to share his grief that Eutyches has made himself estranged from the unity of faith, to inform Julian that the episcopal proceedings have revealed the full detestability of Eutyches’s complaint, and to report that through his legates sent from his side in his stead he has directed to Flavian writings sufficient for the universal Church to know what the Apostolic See holds as divinely handed down concerning the ancient and singular faith.

Leo, bishop, to the most beloved brother Bishop Julian.

Chapter I: Leo Grieves That Eutyches Has Made Himself Estranged from the Unity of Faith

Your beloved’s recent letters, delivered to me, show how greatly we thrive with the spiritual love of the Catholic faith and how great is the joy of heart they give me — that pious hearts are uniting in the same judgment, fulfilling through the teaching of the Holy Spirit among us what the Apostle says: I appeal to you, brothers, by the name of our Lord Jesus Christ, that you all say the same thing, and that there be no divisions among you, but that you be perfect in the same mind and the same judgment (1 Cor. 1:10).

From this unity Eutyches has made himself utterly estranged — if he persists in his perversity and does not yet understand by what bonds of the devil he is held fast, believing that some of the Lord’s priests can be found who would consent to his ignorance and madness. For a long time it was uncertain to us what in him displeased Catholics. While we received no letters from our brother Flavian, and Eutyches himself sought in his writings to make Nestorian heresy appear to be resurging, we were not fully able to discern the source or aim of so harmful a complaint. But once the documentary acts of the episcopal proceedings were brought to us, all that had been veiled by the covering of false complaints was revealed as to how detestable it was.

Chapter II: Leo’s Legates Carry the Doctrinal Standard for the Universal Church to Know

And since the most clement emperor, through his benevolence and piety of soul, wished to judge more diligently the state of one previously deemed honorable and therefore deemed it right to call an episcopal council, through our brothers Julius the bishop, Renatus the presbyter, and my son Hilarus the deacon — whom I have sent from my side in my stead — I have directed to our brother Flavian writings sufficient for the nature of the cause, so that both your beloved and the universal Church may know what we hold as divinely handed down and what we inviolably proclaim concerning the ancient and singular faith which this unlearned assailant has attacked.

Now we ought no longer to omit the part of mercy; yet we judge it fitting for priestly moderation that, if the condemned one corrects himself by full satisfaction, the sentence by which he is bound may be relaxed. But if he chooses to lie in the mire of his own folly, let the decrees stand, and let him share the lot of those whose error he has followed.

Given on the Ides of June, in the consulship of Asturius and Protogenes, most illustrious men.

Source/Reference

Notes / Historical Commentary

Letter XXXIV is the briefer of two letters Leo sent to Julian of Cos on June 13, 449, the other being the much longer Letter XXXV. Julian (Julianus) of Cos was Leo’s closest and most trusted correspondent in the East during the Eutychian crisis and the years that followed. As bishop of a small Aegean island, he held no great institutional position of his own, but his proximity to Constantinople, his bilingualism, and his profound alignment with Leo’s theological and ecclesiological convictions made him indispensable. He served as Leo’s representative and informant in the capital, and is believed to have translated a number of Leo’s letters into Greek for Eastern circulation. The frequency and warmth of Leo’s letters to Julian across the corpus is striking — he is addressed as “most beloved brother” with a consistency that marks him as something closer to a personal agent than a collegial correspondent.

Letter XXXIV is essentially a cover letter: it acknowledges Julian’s recent letter (delivered by the deacon Basilius), reports what Leo has done in response to the Eutychian crisis, and informs Julian that the legates have been dispatched with letters to Flavian sufficient for the whole Church to know what the faith requires. The theological argument is deferred to Letter XXXV; the function of Letter XXXIV is to keep Julian informed and in communication with Rome as the crisis unfolds. The letter’s brevity is itself significant — Julian already knows the essentials, and Leo is ensuring that his most trusted Eastern correspondent has the same information simultaneously with all the other recipients of the June 13 dispatch.

The primacy content is concentrated in a single sentence of Chapter II, which is worth examining carefully. Leo writes that he has sent through his legates — quos ex latere meo vice mea misi — writings to Flavian “sufficient for the nature of the cause, so that both your beloved and the universal Church may know what we hold as divinely handed down.” The claim is structural as much as doctrinal. Leo’s letter to Flavian — the Tome — is not private correspondence between two bishops; it is the doctrinal standard for the universal Church. Julian is being asked to know this because he will need to defend it in Constantinople. The sentence moves from the legation formula (ex latere meo vice mea) to the universal scope of the doctrinal claim (the whole Church is to learn its faith from what Leo has written) in a single breath — the same logic that governs Letters XXXI, XXXII, and XXXIII from different directions.

The reader who wants the full Christological argument will find it in Letter XXXV, which follows immediately in the corpus and addresses the same recipient on the same day. Letter XXXIV is the handshake; Letter XXXV is the theology.