The Holy Trinity is
ineffable
sublime
incomprehensible
yet has been written about here:
[* = I’ve even read it!]
Ancient (up to AD 500)
Augustine of Hippo. On the Trinity. This is St. Augustine’s book-length work on the Holy Trinity.
—. Sermon 52 (#2 of those on the NT). St. Augustine sets out concisely the teaching on the Holy Trinity in ways that would makes sense to his congregation. I haven’t read it, but I’ve read all about it in Hall’s book, cited below.
*Basil the Great. On the Holy Spirit. In this spirited (ha!) treatise, St. Basil defends the deity of the Son and the Spirit and discusses the work of the Person of the Holy Spirit.
*Gregory of Nazianzus. Theological Orations. In clear, logical terms, St. Gregory sets out the orthodox belief about the Holy Trinity, taking the Incarnation as his starting point.
Gregory of Nyssa. On the Holy Trinity.
Medieval (500-1000)
*Boethius. Trinity Is One God not Three Gods.
*John of Damascus. On the Orthodox Faith. Book 1, Chapter 8 is about the Holy Trinity.
Thomas Aquinas. Summa Theologica. Prima Pars, qq. 27-43 deal with the Holy Trinity. It’s complex and Aristotelian.
Modern (1500 to the present)
*Calvin, John. Institutes of the Christian Religion. Book 1, Ch. 13. Here Calvin sets out the basic boundaries of Trinitarian thought and deals with certain heresies.
*Hall, Christopher A. Learning Theology with the Church Fathers. In this book, Hall presents the teachings of the Fathers on various major theological issues, dealing with St. Gregory of Nazianzus and St. Augustine of Hippo on the Trinity on pp. 53-82.
*Humphrey, Edith M. Ecstasy and Intimacy: When the Holy Spirit Meets the Human Spirit. Using Trinitarian theology as the background, Humphrey sets out from technical discussions into the realm of “mystical” or “spiritual” theology and Christian “spirituality”.
*Lewis, C.S. Mere Christianity. In the third section of this classic exposition of the Christian faith, “Beyond Personality”, Dr. Lewis discusses the doctrine of the Most Holy Trinity.
*Tozer, A.W. The Knowledge of the Holy. This penetrating yet “simple” book includes a chapter “The Trinity”.
*Volf, Miroslav. Exclusion & Embrace. Pp. 167-190 deal with the Trinity and gender identity in a helpful and incisive way.
—. After Our Likeness: The Church As the Image of the Trinity. I have read most of this book wherein Volf engages with Zizioulas (below) and Ratzinger (aka Benedict XVI) and seeks to move from Triadology to ecclesiology for free church traditions.
*Zizioulas, John D. Being As Communion. Zizioulas gives a brilliant discussion of the Greek fathers and their contribution to theology and our understanding of the Holy Trinity as well as its ramifications for our lives today.
Now the Catholic Faith is this, / that we worship one God in Trinity, and the Trinity in Unity; Neither confusing the Persons, / nor dividing the Substance. For there is one Person of the Father, another of the Son, / another of the Holy Ghost; But the Godhead of the Father, and of the Son, and of the Holy Ghost is all one, / the glory equal, the majesty co-eternal. Such as the Father is, such is the Son, / and such is the Holy Ghost; The Father uncreated, the Son uncreated, the Holy Ghost uncreated; The Father infinite, the Son infinite, the Holy Ghost infinite; The Father eternal, the Son eternal, the Holy Ghost eternal; And yet there are not three eternals, but one eternal; As also there are not three uncreated, nor three infinites, / but one infinite, and one uncreated. So likewise the Father is almighty, the Son almighty, / the Holy Ghost almighty; And yet there are not three almighties, but one almighty. So the Father is God, the Son God, the Holy Ghost God; And yet there are not three Gods, / but one God.
-from the so-called “Creed of St. Athanasius”
Classically Christian 
[…] 22 06 2010 In the midst of the links to the right, I now have a brief list of Resources on the Holy Trinity! […]
Here are two other resources:
http://www.thriceholy.com
http://forums.delphiforums.com/theholytrinity The Holy Trinity: Discussion & Debate (My own forum focused on the Christian Doctrine of the Trinity, a very orthodox presentation and defense of the Trinity)
Secundus
Hi Secundus! Thank you so much for these resources. 🙂
After reading a bit more throughout your blog, I find you and I have much in common. I am American (and you know, I’m sure Mr Bernard Shaw’s quip about us being “two peoples separated by a common language”), that not withstanding, we have many beliefs and passions in common.
I have an MDiv from an Accredited Interdenominational Seminary with a focus in Church History.
I am Methodist, but my faith is formed and informed by Baptist, Presbyterian, Charismatic, and even Eastern Orthodox traditions.
I, too, have a love for the Scriptures, and a love for the Church Fathers (my favorites being Irenaeus and Justin Martyr…but I also have a strong affinity for such as Origen of Alexandria, and Tertullian… original thinkers who challenged the edges of orthodoxy.)
My more modern influences include Martin Luther (I am a Protestant, afterall), John Calvin (to an extent…I have been on both sides of the Calvinist/Arminian discussion. I have become a bit more Wesleyan-Arminian–as opposed to the classical Dutch Arminianism–so I am closer to Calvin on some matters, but not others), John Wesley (I am Methodist, as I mentioned), and also Karl Barth (his Neo-orthodoxy appeals to me on many levels).
I have also been influenced by the “Paleo-Orthodoxy” of such men as Thomas Ogden and Timothy George (the Dean of Beeson Divinity School, the seminary I attended). These men encouraged me to learn about and read the Church Fathers and study ancient Christian spirituality.
In recent years, I have discovered the exotic and refreshing world of Eastern Orthodoxy through Bishop Kallistos Ware’s book, The Orthodox Church. Much of my understanding of the Trinity and our salvation is informed by the Orthodox Tradition.
I was paid a rare compliment by an online friend-sonetime-critic, who is Russian Orthodox, that if he didn’t know I was a Protestant, he would have sworn that an Orthodox Christian had written my posts on the Trinity on my own blog/discussion forum about the Trinity. High praise from him, let me tell you. (He considers Protestantism to be an heretical offshoot of an heretical Catholic tradition.)
I hold to the Nicene Creed in its original 381AD version… without the unauthorized and theologically questionable filioque addition. (I do not consider the Filioque to be heretical per se, just unnecessarily confusing and divisive).
Anyway, I have found much in your blog that resonates with me. You seem to be a kindred spirit on many levels with like passions for Christianity in its “Classical” expression.
Peace to you,
Secundus