The See of Peter

The Early Church and Peter's Primacy

Letter XCIII, from Pope Leo to the Synod at Chalcedon

Synopsis: Leo writes to the bishops convened at Nicaea — the council later moved to Chalcedon — declaring that neither the necessity of the times nor custom permits his attendance, but that his legates carry his presence and his presidency; that disputes against the divinely inspired faith must be suppressed; and that bishops expelled for orthodoxy must be restored, while the prior Ephesine decrees against Nestorius remain in force.

Leo, bishop, to the holy Synod established at Nicaea, most beloved brothers in the Lord, greetings.

Chapter I: Leo Notes That Neither Time Nor Custom Permits His Attendance but Declares He Will Be Present in His Legates and Preside Through Them

I had desired, most beloved, for the charity of our college, that all bishops of the Lord persist in one devotion to the Catholic faith, not turned aside from the path of truth by favor or by fear of secular powers. But since many things often arise that may give rise to repentance, and the mercy of God surpasses the faults of the erring — suspending punishment so that there may be place for correction — we must embrace the most clement prince’s counsel, full of religion, by which he willed your holy brotherhood to convene for destroying the snares of the devil and for restoring ecclesiastical peace, with the right and honor of the most blessed Apostle Peter preserved. He also invited us by his letters to offer our own presence at the venerable synod — a thing that neither the necessity of the times nor any custom could permit. Nevertheless, in these brothers — Paschasinus and Lucentius, bishops, Bonifacius and Basilius, presbyters — sent by the Apostolic See, let your brotherhood deem me presiding over your synod; my presence not absent from you, since I am now present in my vicars, and have long not been absent from the preaching of the Catholic faith: so that those who cannot be ignorant of what We believe from ancient tradition cannot doubt what We desire.

Chapter II: Leo Declares That Audacious Disputes Against the Divinely Inspired Faith Must Be Suppressed

Wherefore, most beloved brothers, having cast out entirely the audacity of disputing against the divinely inspired faith, let the vain unbelief of the erring cease; nor may it be lawful to defend what it is not lawful to believe. For according to evangelical authorities, the voices of the prophets, and apostolic teaching, it has been most fully and clearly declared — through the letter We sent to Flavian, bishop of blessed memory — what the pious and sincere confession is concerning the mystery of the Incarnation of our Lord Jesus Christ.

Chapter III: Leo Urges Restoration of Bishops Expelled for Their Faith; the Prior Ephesine Decrees Against Nestorius Stand

For since We are not unaware that through wicked rivalries the condition of many Churches has been disturbed, and that very many bishops, because they would not receive the heresy, were driven from their sees and sent into exile, and others substituted in their place: let the remedy of justice be applied to these wounds first, so that no one is so stripped of what is his own that another uses what belongs to another. For if, as We desire, all abandon error, no one’s honor ought to perish; but those who labored for the faith must have their own right fully restored to them. Let the decrees of the prior Ephesine synod, presided over by Cyril, bishop of holy memory, concerning Nestorius in particular, stand firm: lest the impiety then condemned should flatter itself in any respect because Eutyches is justly struck down. For the purity of faith and doctrine, which We preach with the same spirit as our holy Fathers, equally condemns and pursues both Nestorianism and Eutychianism together with their authors.

Fare well in the Lord, most beloved brothers. Dated the sixth day before the Kalends of July, in the consulship of Adelfius, most illustrious man.

Source/Reference

PL 54:935

Notes / Historical Commentary

Letter XCIII is Leo’s formal letter to what became the Council of Chalcedon. It was written to the bishops summoned to Nicaea — the council was still at Nicaea when Leo sent it — and was read aloud at Session I of Chalcedon as Leo’s opening statement of presidency. No other document in the pre-Chalcedon packet carries quite the same weight: it is simultaneously a letter of credence, a presidency claim, a doctrinal directive, and a pastoral program for the council’s work. The reader who wants to understand how Leo understood his relationship to the ecumenical council should begin here.

The presidency claim in Chapter I is stated in terms that leave no ambiguity. Leo declares that he will preside over the synod through his legates: me synodo vestra fraternitas æstimet præsidere — “let your brotherhood deem me presiding over your synod.” He is not asking the bishops to give his legates a respectful hearing. He is telling them that the council’s president is present in its midst, in the persons of Paschasinus, Lucentius, Bonifacius, and Basilius. The phrase non abjuncta a vobis præsentia mea, qui nunc in vicariis meis adsum — “my presence not absent from you, since I am now present in my vicars” — makes the claim still more direct: Leo’s personal presence is not absent because his vicars carry it. This is the logic of the vicariate applied to the council as a whole, and it was enacted precisely as Leo described: at Chalcedon’s first session, Paschasinus announced that Leo was present in the gathering and demanded that Dioscorus — who had presided at the Latrocinium — be removed from the proceedings before they began.

Equally significant, and easily passed over, is the clause beatissimi Petri apostoli jure atque honore servato — “with the right and honor of the most blessed Apostle Peter preserved.” Leo inserts this phrase as the condition on which he accepts the emperor’s convocation. The emperor has the power and the religious zeal to summon a council; Leo’s acceptance of that summons is conditioned on its preserving the Petrine principle intact. The formulation is not deferential to the imperial initiative but structurally prior to it: the council convenes on terms Leo is specifying, and those terms are Petrine. The reader will find this the same structure as Letter LXXXIX, where Leo similarly insists that whatever the emperor does must preserve what belongs to Peter.

The final sentence of Chapter I — “those who cannot be ignorant of what We believe from ancient tradition cannot doubt what We desire” — carries the authority structure into its doctrinal dimension. What the council is to believe is what Rome has believed from ancient tradition; what it is to do is what Rome desires. These are not suggestions. The council is not meeting to determine the faith from scratch; it is meeting in the light of what Leo has already declared in the Tome. Chapter II makes this explicit: the Tome is the measure against which every dispute is to be resolved.

A note on the Constantinople I passage noted in the preceding session: the statement that the First Council of Constantinople “began to be counted among the general councils” only after it received the approval of the Apostolic See appears in the PL apparatus — specifically in Quesnellus’s footnote (a) on col 935 — not in Leo’s body text. Quesnellus was glossing Leo’s use of vere (“truly”) in Cap. I, explaining why a council held without universal summons could still be ecumenical. His explanation invokes the Apostolic See’s confirmatory role as the operative principle. This is a significant Catholic canonical argument, and Quesnellus draws it naturally from the tradition Leo embodies — but the reader should be clear that it is Quesnellus’s synthesis, not Leo’s own formulation. What Leo’s text itself says about conciliar authority is equally pointed: his legates carry his presidency, the Tome is the doctrinal standard, and the council acts under the right and honor of Peter. That is authority enough.