*Note: If you have limited time, read the sources highlighted in green.  

Pseudo-Dionysius the Areopagite
The Divine Names
Mystical Theology

Boethius
Consolation of Philosophy
The Trinity is One God not Three Gods
Against Eutyches and Nestorius
On the Catholic Faith

Benedict of Nursia
The Benedictine Rule
John Climacus
The Ladder of Divine Ascent

Gregory the Great
Homilies (selections)
The Book of Pastoral Rule
On Christian Doctrine and Practice

Maximus the Confessor
The Cosmic Mystery of Christ [read this at least three times. It is arguably the most important book on this list]
Opuscule 7
The Trial of Maximus
On Difficulties in Sacred Scripture
Two Hundred Chapters on Theology
On the Ecclesiastical Mystagogy

• Secondary Source: Nikolaos Loudonikos. A Eucharistic Ontology. [My favorite work on Maximus]

• Secondary Source: Demetrios Bathrellos. The Byzantine Christ. [The best discussion on Maximus the Confessor]

• Secondary Source: Adam Cooper. The Body in St. Maximus the Confessor: Holy Flesh, Wholly Deified. [Great discussion of Maximus’s “Five Divisions” and their subsequent unities]

• Secondary Source: Lars Thunberg. Microcosm and Mediator. [Encyclopedic work on Maximus. No original ideas here, but an outstanding summary of the Nyssa-Maximus tradition]

• Secondary Source: Michel Barnes. Dunamis in the thought of Gregory of Nyssa. [The best discussion on what Gregory means by energy and power]
  
  

John of Damascus
On the Orthodox Faith and Fount of Knowledge
Dialogue between a Muslim and a Christian
Concerning the Divine Images
The Fount of Knowledge
On Heresies
Three Treatises on the Divine Images

Theodore the Studite
On the Holy Icons

Johannes Scotus Eriugena
On Divine Predestination

Photius of Constantinople
Treatise on the Mystagogia of the Holy Spirit
Encyclical Letter to the Archiepiscopal
Sees of the East

John Scotus Eriugena
Division of Nature
God and the Moral Law

Pope Nicholas I
Letter to Archbishop Hincmar of Reims and the Bishops of the Western Empire

Remigius of Lyons (and Florus of Lyons)
Reply to the Three Letters (of Hincmar and Rabanus) – in defense of Gottschalk
On the Universal Ruin of All Humanity through Adam and the Special Redemption of the Elect through Christ
On Steadfastly Holding the Truth of Scripture and Faithfully Following the Authority of the Holy Orthodox Fathers

Paschasius Radbertus
Concerning the Body and Blood of the Lord

Ratramnus
Concerning Christ’s Body and Blood

Simeon the New Theologian
The Discourses
The First-Created Man

Anselm of Canterbury
Monologion
Proslogion
Why God Became Man
On the Incarnation of the Word
On the Procession of the Holy Spirit
On the Virgin Conception and Original Sin
De Concordia: The Compatibility of God’s Foreknowledge, Predestination and Grace with Human Freedom

Anselm of Laon
Fragment on Original Sin
A Question on Original Sin

Peter Abelard
Sic et non (Yes and No)
Exposition of the Epistle to the Romans
History of my Calamities

Bernard of Clairvaux
On Conversion
On Loving God
Sermons on The Song of Songs
On Grace and Free Choice
Steps of Humility and Pride

Hugh of Saint Victor
The Moral Ark of Noah
On the Sacraments of the Christian
Faith
On the Trinity

Peter Lombard
Four Books of Sentences
Commentary on Romans

Hildegard Bingen
The Book of Divine Works

Richard of Saint Victor
Concerning the Trinity
Mystical Comments on the Psalms
Ezekiel’s Vision, Prologue

Stephen Langton
A Question on Original Sin
Fragments on the Morality of Human
Acts

Joachim of Fiore
The Everlasting Gospel

Francis of Assisi
Canticle of the Sun
Later Rule of 1223
The Testament

Albert the Great
On Job
On the Body of the Lord

Bonaventure
The Journey of the Mind to God
Breviloquium
Disputed Questions on the Mystery ofthe Trinity
Retracing the Arts to Theology Commentaries (e.g., Eccl; Jn; Lk)

Thomas Aquinas
Summa Theologiae
Summa Contra Gentiles
Commentaries: Matt; John, Paul’s Epistles; Job
Academic Sermons
Commentary on the Metaphysics

Giles of Rome
On Ecclesiastical Power

Meister Eckhart
Sermons

Dante Alighieri
De Monarchia
Divine Comedy

John Duns Scotus
Opus Oxoniense
Commentary on the Sentences
Questions on Aristotle’s Categories

William of Ockham
Predestination, God’s Foreknowledge, and Future Contingents
Eight Questions on the Power of the Pope
Philosophical Writings (selections)

Robert Holcot
Lectures on the Wisdom of Solomon

Gregory Palamas
Triads in Defense of the Holy
Hesychasts

• Secondary Source: Georgios Mantzaridis. The Deification of Man: St. Gregory Panamas & the Orthodox Tradition.

Thomas Bradwardine
Concerning the Cause of God against Pelagius

John Brevicoxa
A Treatise on Faith, the Church, the Roman Pontiff, and the General Council

Jacob Hoeck
Excerpt from a Letter of Jacob Hoeck to Wessel Gansfort

Wessel Gansfort
From the Letter in Reply to Hoeck by Wessel Gansfort

Julian of Norwich
Revelations of Divine Love

John Huss
Concerning the Church
Exposition of the Faith, the Ten Commandments, and the Lord’s Supper
Letter from Prison (to followers in Bohemia)
On Simony

Thomas a Kempis
The Imitation of Christ

John Wyclif
The Power of the Pope
On the Eucharist
New Testament
On the Pastoral Office

Pope Pius II
Execrabilis

Gabriel Biel
The Circumcision of the Lord

Sylvester Prierias
Word and Sacrament

Cornelisz Hoen
A Most Christian Letter

Cardinal Cajetan, Thomas De Vio
The Celebration of the Mass

Jacobus Faber Stapulensis
Introduction to Commentary on the Psalms
Introduction to Commentaries on Paul’s Letters

Johann von Staupitz
Eternal Predestination and its Execution in Time

Other
Sacrosancta (Council of Constance, 1415)