Church Fathers · Latin · Rome

Leo the Great

Bishop of Rome from 440 to 461, whose letters and preaching join the confession of Christ’s divinity and humanity to worship, pastoral care and the claims of the Roman see.

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Begin with Sermon XXI on Christmas, then read the Tome to Flavian. Letter CVI opens a different question: how Leo understood Constantinople’s rank after Chalcedon.

The correspondence includes sixty-five whole letters attributed to Leo and seven whole incoming documents, alongside summaries and partial material. Neither collection is all of Leo’s surviving work.

Life and historical setting

Leo served the Roman Church as a deacon before becoming its bishop in 440. Benedict XVI’s account places his election during a mission to Gaul and his death in 461. His ministry unfolded amid imperial weakness and threats to Rome. Letters and sermons show how doctrinal controversy, local pastoral needs and wider church relations met in his office. [1]

Benedict recalls Leo’s encounter with Attila in 452 and his intervention during the Vandal attack on Rome in 455. These episodes belong to his public reception as a bishop engaged in the city’s survival. The linked catechesis gives a modern Catholic telling; the writings below offer more direct access to his theological and pastoral voice. [1]

Named Catholic and Orthodox reception

Benedict XVI presents Leo as a Doctor of the Church. The OCA commemorates him on February 18 and honours his defence of Christ’s divinity and humanity. These are named Catholic and Eastern Orthodox witnesses to his reception. Shared honour for Leo still leaves room to examine how his Roman claims and particular interventions are understood. [1] [2]

The Tome to Flavian was read at Chalcedon in 451. The council’s definition receives Leo’s letter alongside earlier creedal and patristic witnesses in its confession of one Christ in two natures. Read that reception within the council’s argument; a papal letter and a conciliar definition are related texts with different settings. The Tome · Chalcedon’s definition and historical notes

Major writings and a reading path

Sermons for the Christian year

Leo’s preaching brings the confession of Christ into the lives of his hearers. In Sermon XXI the joy of Christmas leads through an account of the incarnation to an appeal about conduct, baptism and membership in Christ. Follow all three sections: the closing exhortation grows out of the claim that the same Lord is truly divine and truly human. Read Sermon XXI

Feltoe’s historical English edition translates forty-eight selected sermons, retaining their historical numbers. Gaps between numbers do not mean that a missing sermon has been translated elsewhere in this collection. Use the reader’s contents to follow a complete selected sermon before comparing it with another feast or theme. Read the sermon selection

Letters and the Tome to Flavian

Letter XXVIII addresses Flavian of Constantinople about Eutyches and the incarnation. Leo argues through the creed and scriptural testimony before explaining how the properties of divinity and humanity belong to the one Christ. The polemic and its intended recipient matter: this is an intervention in a controversy, with an argument to follow beyond its later title, “the Tome.” Read the complete translated Letter XXVIII

The correspondence collection mixes different kinds of material. Sixty-five letters attributed to Leo and seven incoming documents are translated in full. Other numbered positions offer editorial summaries, referrals or partial text. The historical sequence reaches 173 positions, but that is not a count of complete letters written by Leo. In particular, Letter CLXV’s Second Tome and attached florilegium are omitted; a notice about them does not supply their text. Browse the correspondence and its contents

Edition notes

Letter LIII has an incoming fragment notice without a translated letter body. The incoming Letter CI supplies chapter III and an editorial summary, rather than the whole document. Historical numbering, authorship and the amount translated are separate questions. The collection’s attributions are retained without presenting them as a fresh critical judgment on every document.

Letter CVI and the rank of Constantinople

In Letter CVI Leo congratulates Anatolius on doctrinal agreement while rebuking what he regards as an improper claim to rank. He appeals to the Nicene canons and the standing of Alexandria and Antioch. This juxtaposition makes the letter useful for studying the distinction between agreement about Christ and disagreement about church order. His account is a participant’s argument in that dispute. Read the complete Letter CVI and notes

Compare the letter with Chalcedon’s Canon XXVIII and its historical commentary. Ask how the canon explains Constantinople’s privileges and how Leo contests them. The study of Constantinople’s rank follows that comparison; Roman primacy examines a wider set of claims.

Reading Christology and pastoral care together

Sermon XXI and the Tome share an insistence on the reality of Christ’s humanity. The sermon draws hearers toward joy and a transformed life; the letter presses a disputed confession with scriptural and doctrinal reasoning. Compare their use of Christ’s birth and human nature without assuming that the differences of audience and purpose disappear. Sermon XXI · Letter XXVIII

The studies of Chalcedon’s natures and person and Theotokos provide further points of comparison. Read the historical translation first, and keep Leo’s prose distinct from the editor’s explanations and later theological judgments.

The English editions

The larger collections use Charles Lett Feltoe’s historical English translation in the 1895 NPNF volume held by Wellesley College Library and digitized by the Internet Archive. The separate Letter CVI remains available through its established reader link. A second route to the same letter does not add another letter to Leo’s works. [3]

Edition notes

The larger readings were derived from the print scan and mechanical text recognition, with targeted corrections. They have not been proofread word by word; consult the scan for doubtful readings. Historical headings, summaries, incoming documents and notes retain their own roles. Forty-eight sermons and the selected correspondence do not constitute a complete Leo corpus.

Sources and further reading

  1. Benedict XVI, General Audience, 5 March 2008: Saint Leo the Great. Catholic reception and a brief account of Leo’s episcopate.
  2. Orthodox Church in America, Saint Leo the Great, Pope of Rome. Named Orthodox reception and February 18 commemoration.
  3. NPNF, second series XII: Feltoe’s historical English Leo translation (1895), Wellesley College Library scan. Source print for the larger sermon and correspondence collections and their historical apparatus.