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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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Early Christian letters and rules
- Apostolical Canons, historical introduction and eighty-five canons — Apostolical Canons (traditional title; compilation disputed)
- First Epistle of Clement to the Corinthians, complete Chapters XLII–XLIV — Clement of Rome (traditional attribution; letter of the Roman church)
- Epistle to the Romans, complete shorter Greek recension and attached edition notes — Ignatius of Antioch
Creeds, councils and canons
- Trent Session IV — Decree concerning the canonical Scriptures (Waterworth 1848) — Council 19
- Creed150: The Holy Creed of the 150 Fathers, complete Percival edition dossier — Council of Constantinople I (received confession; transmission qualified)
- Chalcedon Definition: complete scoped Percival historical edition dossier — Council of Chalcedon (decree); Anatolius and historical edition commentators distinguished
- Chalcedon Session I: complete scoped Percival historical edition extract — Chalcedon Session I participants; attributed speeches and historical edition notes distinguished
- Constantinople III: Definition of Faith (historical edition) — Third Council of Constantinople; edition glosses distinguished
- Constantinople I Canon III, complete historical canon unit with commentary — Constantinople I
- Chalcedon Canon XXVIII, complete historical canon unit with commentary — Chalcedon
- Synod of Antioch in Encæniis (341), introduction, letter and twenty-five canons — Synod of Antioch in Encæniis (historical edition attribution)
- Lateran V: Pastor aeternus gregem (1516; complete named Latin bull in Turin edition) — Leo X, sacro approbante Concilio (Lateran V); later editorial framing excluded
- Nicaea I canon VIII with complete historical notes and excursus — First Council of Nicaea; historical apparatus separately attributed
- Nicaea I canon XI with complete historical notes and excursus — First Council of Nicaea; historical apparatus separately attributed
- Nicaea I canon XIII with complete historical notes and excursus — First Council of Nicaea; historical apparatus separately attributed
- Sardica: complete scoped historical-edition canons dossier — Synod of Sardica; historical edition apparatus distinguished
- Nicaea I: Canon VIII with historical commentary and excursus — First Council of Nicaea; separate epitome and later edition voices retained
- Nicaea I: Canon XIX with historical commentary and excursus — First Council of Nicaea; separate epitome and later edition voices retained
- Session XIII: Honorius second-letter fragments and separate Pyrrhus material (Latin) — Council Acts narration, with Honorius and separate Pyrrhus excerpts
- The Decree of the Holy, Great, Ecumenical Synod, the Second of Nice — Second Council of Nicaea (787)
- Council of Trent, Session XIII: Eucharist decree, Chapters I–VIII and Canons I–XI (Waterworth, 1848) — Council of Trent
- Nicaea I, canon VI — first sentence only (Percival edition, 1900) — First Council of Nicaea (325)
- Vatican I — Pastor aeternus, Chapters I–IV (English version from Manning’s volume, in Schaff 1896) — Pius IX with the approval of Vatican I (1870)
- Constance: Haec sancta (five-declaration core, Mansi 1784 / Welter 1903) — Council of Constance, session V; printed marginal apparatus from the historical collection
- Constantinople 1895: patriarchal and synodal reply (Metallinos 1896, selected §§XVI and XIX) — Anthimus VII and the synod of Constantinople
Later confessions and catechisms
- Confession of Dositheus, complete Question III on Scripture — Synod of Jerusalem (1672)
- Opposing appendix confession, complete Question III and apparatus — Confession published with the name of Cyril Lucar
- Confession of Dositheus, complete Decree I and attached edition notes — Synod of Jerusalem (1672)
- Confession of Dositheus, complete Decree II and attached edition notes — Synod of Jerusalem (1672)
- Confession of Dositheus, complete Decree XIII and attached edition notes — Synod of Jerusalem (1672)
- Confession of Dositheus, complete Decree XIV and attached edition notes — Synod of Jerusalem (1672)
- Confession of Dositheus, complete Decree XVII and attached edition notes — Synod of Jerusalem (1672)
- Confession of Dositheus, complete Decree XVIII and attached edition notes — Synod of Jerusalem (1672)
- Longer Catechism, complete On the Eighth Article — Philaret of Moscow; Russian Holy Synod catechism
- Longer Catechism, complete On the Communion — Philaret of Moscow; Russian Holy Synod catechism
Theology, preaching and Christian life
- De Decretis or Defence of the Nicene Definition — Athanasius of Alexandria
- Letter of Eusebius of Cæsarea to the people of his Diocese — Eusebius of Caesarea
- Oration 31: The Fifth Theological Oration — On the Holy Spirit — Gregory of Nazianzus
- Letter II: Basil to Gregory — Basil of Caesarea
- The Demonstration of the Apostolic Preaching — Irenaeus of Lyons
- Letter 101: To Cledonius the Priest Against Apollinarius — Gregory of Nazianzus
- Second Letter to Nestorius (edition Epist. iv.) — Cyril of Alexandria
- Enchiridion: Faith, Hope and Love — Augustine of Hippo
- A Treatise on Grace and Free Will — Augustine of Hippo
- XIII. The Third Conference of Abbot Chæremon. — John Cassian
- Exposition of the Orthodox Faith, Book IV, Chapter XVI: Concerning Images — John of Damascus
- On the Spirit — Basil of Caesarea
- Leo Letter CVI to Anatolius, complete historical letter and notes — Leo of Rome
- Letter53 to Paulinus, complete historical English letter — Jerome of Stridon
- Mystagogical Catechesis V (Lecture XXIII): On the Sacred Liturgy and Communion — Cyril of Jerusalem (traditional attribution)
- To Cornelius in Exile, Concerning His Confession (ANF Epistle LVI) — Cyprian of Carthage
- On Nature and Grace — Augustine of Hippo
- An Exact Exposition of the Orthodox Faith — John of Damascus
- From Festal Letter 39, complete edition-defined extract and notes — Athanasius of Alexandria
- Mystagogical Catechesis IV (Lecture XXII): On the Body and Blood of Christ — Cyril of Jerusalem (traditional attribution)
- On the Mysteries — Ambrose of Milan
- Against Heresies III.3, complete chapter and historical notes — Irenaeus of Lyons
- On the Unity of the Church, complete treatise and historical notes — Cyprian of Carthage
- To Fidus, on the Baptism of Infants (ANF Epistle LVIII) — Cyprian and episcopal colleagues
- Oration 40: On Holy Baptism — Gregory of Nazianzus
- On the Lapsed, complete historical treatise and edition notes — Cyprian of Carthage
- Pontius: The Life and Passion of Cyprian, Bishop and Martyr — Pontius the Deacon (historical edition attribution)
- To Stephen, Concerning a Council (ANF Epistle LXXI) — Cyprian and colleagues (collective greeting)
- Roman clergy to Cyprian (complete ANF Epistle XXX) — Roman presbyters and deacons at Rome
- To Antonianus about Cornelius and Novatian (complete ANF Epistle LI) — Cyprian of Carthage
- Julius to the Eusebian bishops at Antioch: complete scoped letter chapter — Julius of Rome, transmitted within Athanasius
- On the Merits and Forgiveness of Sins and Baptism of Infants, Book I — Augustine of Hippo
- Homily X on Romans — John Chrysostom
- Church History III.25, complete historical chapter and notes — Eusebius of Caesarea
- Nisibene Hymn I, complete historical English hymn — Ephrem the Syrian
- On Not Three Gods: To Ablabius, complete historical work and edition notes — Gregory of Nyssa
- Martyrdom of Polycarp: the Smyrna church account (complete historical edition unit) — The church at Smyrna (transmitted account; copyist additions separately identified)
- Basil: Letter 188 to Amphilochius, Canonica Prima (complete historical edition) — Basil of Caesarea
- Augustine: On Baptism, Against the Donatists, Book I (complete historical edition) — Augustine of Hippo
- Honorius I: first letter to Sergius (complete published Latin unit) — Honorius I
- Attributed to Leo II: letter to Constantine (complete published Latin version) — Attributed to Leo II
- Leo II: letter to the bishops of Spain (complete published Latin unit) — Leo II
- Attributed to Leo II or Benedict II: letter to Ervigius (complete published Latin unit) — Attributed to Leo II; historical alternative attribution to Benedict II
- Church History V.23–25, complete chapters and notes — Eusebius of Caesarea
- Life of Constantine III.17–20, imperial letter and complete notes — Eusebius of Caesarea
- Homilia I: De pace ad invicem servanda — Gregory Palamas
- Liber asceticus, historical Latin dialogue and attached edition apparatus — Maximus the Confessor
- Commonitory, complete Chapter II — Vincent of Lérins
- Commonitory, complete Chapter XXIII — Vincent of Lérins
- Summa theologiae I.1.2 — complete main answer only (English Dominican Province, 1920) — Thomas Aquinas
- Summa theologiae III.75.4 — final paragraph of the main answer (English Dominican Province, 1914) — Thomas Aquinas
- Summa theologiae III.83.1 — complete main answer only (English Dominican Province, 1914) — Thomas Aquinas
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