The Council and the Tome

The Fourth Ecumenical Council met at Chalcedon in 451, the largest council of the ancient Church, and there the Tome of Leo was read into the record to the cry that “Peter has spoken through Leo.” This file examines what that acclamation did and did not mean: the reading of the Tome and its reception; the crucial fact that the assembled fathers did not simply accept the document on Roman authority but scrutinized it against the letters of Cyril of Alexandria, because some Illyrian and Palestinian bishops feared three of its passages smacked of Nestorianism; the two readings of this episode — the Roman maximal reading of papal voice, reported accurately in its own terms, and the Orthodox conciliar reading of consonance with Cyril, in which the Church herself stands — set out per Methodology §4; and the Definition of Chalcedon, in which the language of Cyril, Leo, and Flavian was woven into one confession.

Tradition: Pan-Orthodox (Church Father / Latin)

The Fourth Ecumenical Council

The Council of Chalcedon, the Fourth Ecumenical Council, was convened by the Emperor Marcian and met across the Bosphorus from Constantinople at Chalcedon (modern Kadıköy) from 8 October to 1 November 451. It was the largest council of the ancient Church: the sources transmit a figure of around 520 to 630 bishops, the great majority of them Eastern, with the Latin West represented chiefly by the legates of Pope Leo I — Paschasinus of Lilybaeum, Lucentius, and the priest Boniface — who presided in Leo’s name alongside the lay imperial commissioners who chaired the sessions and kept order (Price & Gaddis, The Acts of the Council of Chalcedon, TTH 45, vol. 1, 1–85; Sellers, The Council of Chalcedon, 103–131). The council had been summoned to repair the wreckage of the “Robber Council” of Ephesus (449), where Dioscorus of Alexandria had rehabilitated the archimandrite Eutyches, deposed Flavian of Constantinople, and refused even to allow Leo’s Tome to be read. Chalcedon reversed all of this: Eutyches stood condemned, Flavian was vindicated posthumously, and Dioscorus himself was deposed — significantly, on disciplinary rather than explicitly doctrinal grounds — at the council’s first session (Grillmeier, Christ in Christian Tradition, vol. 2/1, 107–148).

The Reading of the Tome

The Tome of Leo — Leo’s dogmatic letter to Flavian of Constantinople of 449 (Leo, Ep. 28; PL 54:755–782; trans. NPNF 2nd ser. 12) — was read into the acts at the second session, on 10 October 451. Its argument was a lucid Latin statement of the two natures in the one person: the Son of God was born, suffered, and died as true man while remaining true God, the integrity of each nature preserved within the single subject, so that “each form does what is proper to it in communion with the other” (agit enim utraque forma cum alterius communione quod proprium est). To the assembled fathers this was the antithesis of Eutyches, who had confused the natures, and of Nestorius, who had divided the subject. When the reading was finished, the acta record the celebrated acclamation: “This is the faith of the fathers! This is the faith of the apostles! … Peter has spoken thus through Leo! … Cyril taught thus! … Leo and Cyril taught the same thing!” (ACO tom. II; Price & Gaddis, vol. 2, session II). The cry “Peter has spoken through Leo” has reverberated through fifteen centuries of controversy over what the council meant by it.

The Scrutiny Against Cyril

Here the most important and least advertised fact of the council must be set down, because it governs the whole reading of the acclamation. The fathers did not simply receive the Tome on Leo’s authority. The acclamation was not the end of the matter but the beginning of an examination. A body of bishops, chiefly from Illyricum and Palestine — those who had earlier inclined to Dioscorus — raised the objection that three passages of the Tome read like the Christology of Nestorius, because Leo spoke of each “form” or nature as the distinct subject of its proper operations, which to a Cyrilline ear threatened to make two acting agents of the one Christ (Price & Gaddis, vol. 2, session II, with the translators’ notes; Sellers, 254–260).

The council’s response is decisive for understanding its mind. The doubtful passages were tested against the letters of Cyril of Alexandria, the council’s already-acknowledged standard of orthodoxy — above all the Second Letter to Nestorius (Cyril, Ep. 4) and the Letter to John of Antioch embodying the Formula of Reunion of 433 (the Laetentur caeli, Ep. 39). The deacon Aetius of Constantinople read out the relevant Cyrilline passages and reconciled the first two contested sentences of the Tome with Cyril’s teaching; the remaining difficulty was addressed in the same Cyrilline frame, and the doubting bishops were given a delay — the sources speak of a span of several days — for instruction before they returned to declare that their hesitation was resolved: “None of us doubts” (Price & Gaddis, vol. 2, session II; Grillmeier, vol. 2/1, 195–235). The Tome was received as orthodox because it was judged consonant with Cyril — not in spite of Cyril, and not on the strength of Leo’s see alone.

Two Readings of “Peter Has Spoken Through Leo”

The episode has received two readings, and per Methodology §4 both are given here with their sources — the Roman accurately in its own terms, the conciliar as the reading in which the Orthodox Church herself stands.

The Roman maximal reading takes the acclamation at full weight. On this account the council’s cry “Peter has spoken through Leo” is a recognition that the successor of Peter, by the charism of his see, articulated the apostolic faith with an authority the council could only ratify; that the Tome arrived as a doctrinal norm and the bishops’ task was to acknowledge it; and that the subsequent comparison with Cyril was confirmatory rather than constitutive — a demonstration, for the benefit of the doubters, of a Roman orthodoxy never genuinely in question. The later Latin tradition would read Chalcedon as a signal instance of Rome teaching and the East receiving (on the development of this reading, Wessel, Leo the Great and the Spiritual Rebuilding of a Universal Rome, 285–321).

The Orthodox conciliar reading takes the scrutiny as load-bearing. On this account the very fact that the Tome was examined — that bishops could voice doubts, that those doubts had to be answered, that the answer was Cyril and not Peter — shows that the Tome’s authority at Chalcedon rested on its agreement with the conciliar faith already received, not on raw papal fiat. The acclamation “Peter has spoken through Leo” is then read in its own immediate context, where it is completed by “Cyril taught thus” and “Leo and Cyril taught the same thing”: Leo is acclaimed because he agrees with Cyril, and the test of that agreement was applied by the council itself. On this reading the council honors Leo precisely as a great patristic witness whose document passed the council’s own examination, and the maximal inference — that Rome’s voice is by itself the rule of faith — is exactly what the scrutiny against Cyril forecloses (Meyendorff, Christ in Eastern Christian Thought, 165–187; Price & Gaddis, vol. 1, 56–75). [Disputed: whether the conciliar examination of the Tome qualifies the authority claimed in “Peter has spoken through Leo” — the Orthodox conciliar reading (Meyendorff, Christ in Eastern Christian Thought, 165–187; Price & Gaddis, vol. 1, 56–75) — or merely confirms a Roman norm not really in doubt — the Latin maximal reading (Wessel, Leo the Great, 285–321) — is the standing interpretive divide, and the same acta sustain both.]

The Definition of Chalcedon

The doctrinal labor of the council came to its term at the fifth session, on 22 October 451, with the promulgation of the Definition of Chalcedon. The emperor and the commissioners had pressed for a written formula; a first draft was rejected by the legates and others as insufficiently guarded against Eutyches, and a committee redrafted it. The result was not the work of any single author but a deliberate weaving together of the council’s authorities. From Cyril came the affirmation of the one Christ, one hypostasis, the Theotokos, and the language of the Formula of Reunion; from Flavian’s confession at the Home Synod of 448 came the formula of Christ “in two natures”; and from Leo’s Tome came the insistence on the integrity and proper operation of each nature within the one person (Sellers, 207–253; Grillmeier, vol. 2/1, 235–273).

The Definition confesses one and the same Christ, Son, Lord, Only-begotten, “acknowledged in two natures (en dyo physesin), without confusion, without change, without division, without separation” (asynchytōs, atreptōs, adiairetōs, achōristōs) — the distinction of the natures in no way removed by the union, but rather the property of each nature preserved and concurring into one person (prosopon) and one hypostasis (hypostasis), not parted or divided into two persons, but one and the same Son and Only-begotten God the Word, the Lord Jesus Christ (Definition of Chalcedon; ACO tom. II; trans. in Price & Gaddis, vol. 2, session V). The four adverbs guard against Eutyches on one flank and Nestorius on the other: “without confusion, without change” denies the mingling or absorption of the natures; “without division, without separation” denies their parceling out between two subjects. The phrase “in two natures,” en dyo physesin, is the very hinge on which the council’s whole achievement — and, as the next file shows, its enduring fracture — would turn.

What Chalcedon Settled

For the Eastern Orthodox tradition Chalcedon is the council that fixed the grammar of Christology: the one Lord Jesus Christ, perfect in Godhead and perfect in manhood, truly God and truly man, one hypostasis in two natures, the bond of the Cappadocian distinction between physis and hypostasis now made the load-bearing structure of the confession of Christ. Leo’s Tome stands within that settlement not as its sovereign source but as one of its three confessed witnesses, received because it was found to teach what Cyril taught and what Flavian confessed. The council that cried “Peter has spoken through Leo” is the same council that proved the saying by Cyril’s letters — and it is in the tension between those two acts that both the Latin and the Orthodox readings of Chalcedon have ever since been rooted.

References

Leo the Great, Letter to Flavian (the Tome), Ep. 28; PL 54:755–782; trans. Charles Lett Feltoe, Nicene and Post-Nicene Fathers, 2nd ser., vol. 12 (New York, 1895).
Acta Conciliorum Oecumenicorum, tom. II, ed. Eduard Schwartz (Berlin–Leipzig, 1932–1938).
The Definition of Chalcedon (451), session V; in ACO tom. II.
Cyril of Alexandria, Second Letter to Nestorius (Ep. 4) and Letter to John of Antioch (Laetentur caeli, Ep. 39).
Richard Price and Michael Gaddis, The Acts of the Council of Chalcedon, Translated Texts for Historians 45, 3 vols. (Liverpool: Liverpool University Press, 2005).
Robert V. Sellers, The Council of Chalcedon: A Historical and Doctrinal Survey (London: SPCK, 1953).
Aloys Grillmeier, Christ in Christian Tradition, vol. 2, part 1, trans. Pauline Allen and John Cawte (London: Mowbray, 1987).
John Meyendorff, Christ in Eastern Christian Thought (Crestwood, NY: SVS Press, 1975).
Susan Wessel, Leo the Great and the Spiritual Rebuilding of a Universal Rome (Leiden: Brill, 2008).