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Patristic writings
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- Who is Christ?
Athanasius and Eusebius on the wording of Nicaea.
- Why venerate images?
Read John of Damascus alongside Basil and named Catholic and Orthodox explanations.
- How do grace and freedom meet?
Augustine and Cassian on the beginning of good willing.
- What does apostolic succession preserve?
Irenaeus, Cyprian and Augustine on teaching, office and communion.
Read the included historical texts, or choose “Include external sources” to find works hosted elsewhere. Complete works, chapters and excerpts are distinguished. Edition and reuse notes accompany each included text.
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Creeds, councils and canons
Council decrees, canons and their historical edition dossiers.
- Apostolical Canons, historical introduction and eighty-five canons · English
- Trent Session IV — Decree concerning the canonical Scriptures (Waterworth 1848) · English
- Creed150: The Holy Creed of the 150 Fathers, complete Percival edition dossier · English
- Chalcedon Definition: complete scoped Percival historical edition dossier · English
- Chalcedon Session I: complete scoped Percival historical edition extract · English
- Constantinople III: Definition of Faith (historical edition) · English
- Constantinople I Canon III, complete historical canon unit with commentary · English
- Chalcedon Canon XXVIII, complete historical canon unit with commentary · English
- Synod of Antioch in Encæniis (341), introduction, letter and twenty-five canons · English
- Lateran V: Pastor aeternus gregem (1516; complete named Latin bull in Turin edition) · Latin
- Nicaea I canon VIII with complete historical notes and excursus · English
- Nicaea I canon XI with complete historical notes and excursus · English
- Nicaea I canon XIII with complete historical notes and excursus · English
- Sardica: complete scoped historical-edition canons dossier · English
- Nicaea I: Canon VIII with historical commentary and excursus · English
- Nicaea I: Canon XIX with historical commentary and excursus · English
- Session XIII: Honorius second-letter fragments and separate Pyrrhus material (Latin) · Latin
- The Decree of the Holy, Great, Ecumenical Synod, the Second of Nice · English
- Council of Trent, Session XIII: Eucharist decree, Chapters I–VIII and Canons I–XI (Waterworth, 1848) · English
- Nicaea I, canon VI — first sentence only (Percival edition, 1900) · English
- Vatican I — Pastor aeternus, Chapters I–IV (English version from Manning’s volume, in Schaff 1896) · English
- Constance: Haec sancta (five-declaration core, Mansi 1784 / Welter 1903) · Latin
- Constantinople 1895: patriarchal and synodal reply (Metallinos 1896, selected §§XVI and XIX) · English
- Constantinople II: complete Sentence of the Synod and fourteen Capitula, with attached historical notes · English
- Trullo Canon CII (102), complete canon and Ancient Epitome · English
- Constantinople 869–870, canon 21 (historical Latin) · Latin
- Constantinople 869–870, canon 22 (historical Latin) · Latin
- Constantinople 869–870, canon 25 (historical Latin) · Latin
- Constantinople 879–880, session III: Commonitorium caput 10 and responses (historical Latin) · Latin
- Constantinople 879–880, session III: Commonitorium chapters 4–9, contextual unit (historical Latin) · Latin
- Constantinople 879–880, session III: reported Photios speech and introduction to reading (historical Latin) · Latin
- Council of Trent, Session XIV, complete Penance Chapter VI and attached notes (Waterworth1848) · English
Letters and pastoral counsel
Letters, including extracts and letters transmitted within other works.
- First Epistle of Clement to the Corinthians, complete Chapters XLII–XLIV · English
- Epistle to the Romans, complete shorter Greek recension and attached edition notes · English
- Letter of Eusebius of Cæsarea to the people of his Diocese · English
- Letter II: Basil to Gregory · English
- Letter 101: To Cledonius the Priest Against Apollinarius · English
- Second Letter to Nestorius (edition Epist. iv.) · English
- Leo Letter CVI to Anatolius, complete historical letter and notes · English
- Letter53 to Paulinus, complete historical English letter · English
- To Cornelius in Exile, Concerning His Confession (ANF Epistle LVI) · English
- From Festal Letter 39, complete edition-defined extract and notes · English
- To Fidus, on the Baptism of Infants (ANF Epistle LVIII) · English
- To Stephen, Concerning a Council (ANF Epistle LXXI) · English
- Roman clergy to Cyprian (complete ANF Epistle XXX) · English
- To Antonianus about Cornelius and Novatian (complete ANF Epistle LI) · English
- Julius to the Eusebian bishops at Antioch: complete scoped letter chapter · English
- Basil: Letter 188 to Amphilochius, Canonica Prima (complete historical edition) · English
- Honorius I: first letter to Sergius (complete published Latin unit) · Latin
- Attributed to Leo II: letter to Constantine (complete published Latin version) · Latin
- Leo II: letter to the bishops of Spain (complete published Latin unit) · Latin
- Attributed to Leo II or Benedict II: letter to Ervigius (complete published Latin unit) · Latin
- Letter of Cyril to John of Antioch (433; complete letter in NPNF XIV) · English
- Vigilius to Eutychius: complete Decretal Letter with historical synopsis, genuineness discussion and notes · English
- Leo’s letters: Feltoe’s complete historical English selection · English
Sermons, catecheses and hymns
Individual sermons, teaching addresses and poetry.
- Oration 31: The Fifth Theological Oration — On the Holy Spirit · English
- Mystagogical Catechesis V (Lecture XXIII): On the Sacred Liturgy and Communion · English
- Mystagogical Catechesis IV (Lecture XXII): On the Body and Blood of Christ · English
- Oration 40: On Holy Baptism · English
- Homily X on Romans · English
- Nisibene Hymn I, complete historical English hymn · English
- Homilia I: De pace ad invicem servanda · Latin
- Oration XLV: The Second Oration on Easter (complete oration and attached historical notes) · English
- Leo’s sermons: Feltoe’s complete historical English selection · English
Treatises and theological dialogues
Doctrinal and spiritual arguments; titles distinguish whole works from selected books or chapters.
- De Decretis or Defence of the Nicene Definition · English
- The Demonstration of the Apostolic Preaching · English translated from Armenian; Greek editorial apparatus
- Enchiridion: Faith, Hope and Love · English
- A Treatise on Grace and Free Will · English
- XIII. The Third Conference of Abbot Chæremon. · English
- Exposition of the Orthodox Faith, Book IV, Chapter XVI: Concerning Images · English
- On the Spirit · English
- On Nature and Grace · English
- An Exact Exposition of the Orthodox Faith · English
- On the Mysteries · English
- Against Heresies III.3, complete chapter and historical notes · English
- On the Unity of the Church, complete treatise and historical notes · English
- On the Lapsed, complete historical treatise and edition notes · English
- On the Merits and Forgiveness of Sins and Baptism of Infants, Book I · English
- On Not Three Gods: To Ablabius, complete historical work and edition notes · English
- Augustine: On Baptism, Against the Donatists, Book I (complete historical edition) · English
- Liber asceticus, historical Latin dialogue and attached edition apparatus · Latin
- Commonitory, complete Chapter II · English
- Commonitory, complete Chapter XXIII · English
- On the Incarnation, complete sections8–10 with attached notes · English
- City of God X, complete chapters5–6 with attached notes · English
- Institutes: Gibson’s historical English print, preface and eleven translated books · English
- Conferences: Gibson’s historical English print, three prefaces and twenty-two dialogues · English
- On the Incarnation against Nestorius: Gibson’s historical English print, all seven books · English
Historical accounts and martyrdoms
Historical narratives, lives and accounts of martyrdom.
- Pontius: The Life and Passion of Cyprian, Bishop and Martyr · English
- Church History III.25, complete historical chapter and notes · English
- Martyrdom of Polycarp: the Smyrna church account (complete historical edition unit) · English
- Church History V.23–25, complete chapters and notes · English
- Life of Constantine III.17–20, imperial letter and complete notes · English
Later confessions and catechisms
Selected sections from later confessional and catechetical texts.
- Confession of Dositheus, complete Question III on Scripture · English
- Opposing appendix confession, complete Question III and apparatus · English
- Confession of Dositheus, complete Decree I and attached edition notes · English
- Confession of Dositheus, complete Decree II and attached edition notes · English
- Confession of Dositheus, complete Decree XIII and attached edition notes · English
- Confession of Dositheus, complete Decree XIV and attached edition notes · English
- Confession of Dositheus, complete Decree XVII and attached edition notes · English
- Confession of Dositheus, complete Decree XVIII and attached edition notes · English
- Longer Catechism, complete On the Eighth Article · English
- Longer Catechism, complete On the Communion · English
- Confession of Dositheus, complete Decree III and attached edition notes · English
- Confession of Dositheus, complete Decree IX and attached edition note · English
Scholastic questions
Complete articles and shorter excerpts from Aquinas’s Summa; each title identifies the scope of its selection.
- Summa theologiae I.1.2 — complete main answer only (English Dominican Province, 1920) · English
- Summa theologiae III.75.4 — final paragraph of the main answer (English Dominican Province, 1914) · English
- Summa theologiae III.83.1 — complete main answer only (English Dominican Province, 1914) · English
- Summa theologiae I.23, complete article 3 (English Dominican Province, 1920) · English
- Summa theologiae I.23, complete articles 5–6 (English Dominican Province, 1920) · English
- Summa theologiae III.48, complete articles2–4 (English Dominican Province, 1914) · English
- Summa theologiae III.52, complete article 2 (English Dominican Province, 1914) · English
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