Big names like Thomas Aquinas and St. Augustine of Hippo are go-tos if you want to do some spiritual and theological reading. But why not add some variety to your spiritual diet by turning to some heavy-hitters from the East? These Church Fathers haven’t quite made as big an impact in the Latin world as they have in the Byzantine, but their wisdom and insight is no less valuable for Christians of every rite. Here are five Eastern Fathers you need to add to your theological library:
1. St. Basil the Great of Caesarea
Known in the Eastern Churches as one of the Three Holy Hierarchs, St. Basil came from a fourth-century family that churned out an unusually high number of saints. Both his maternal grandparents are venerated, along with his mother Emilia, his sister Macrina, and his brothers; Gregory, Peter, and Naucratius. He is considered one of the founders of structured communal monastic life in the East, and authored a rule that is still in use by both Byzantine Catholic and Eastern Orthodox monastics today. Basil was also an accomplished preacher, and most of his extant writings are sermons–perfect for those seeking practical spiritual guidance.
His most famous work is The Hexameron, a series of nine sermons on the six days of Creation that has less to do with modern notions of Young Earth Creationism and more with praising the beauty and spiritual worth of the natural, material world. In addition to being an excellent preacher, St. Basil was also a champion of social justice, and started what is widely considered to be the first functioning hospital, as well as a complex of soup kitchens, hospices, and housing in his native Caesarea. He cared deeply for the poor, and not only gave to them from his personal inheritance, but strove to create a more compassionate society where the sick and poverty-stricken could be taken care of. His various homilies on the treatment of the poor, and the restructuring of society to ease poverty, are not to be overlooked.
Major Works:Â On the Holy Spirit, The Hexameron, Asketika
“I want creation to penetrate you with so much admiration that everywhere, wherever you may be, the least plant may bring to you the clear remembrance of the Creator. If you see the grass of the fields, think of human nature, and remember the comparison of the wise Isaiah. “All flesh is grass, and all the goodliness thereof is as the flower of the field.'”
2. St. Gregory of Nyssa
St. Basil’s younger brother and another of the Three Holy Hierarchs, St. Gregory was bishop of Nyssa and took over many ecclesiastical duties in Pontus after Basil died. His career as bishop was often tumultuous, and he spent most of his time trying to effect the reconciliation of various ideological and heretical sects.  His writings staunchly defended the Trinity as “one in essence”, and he also advocated for the manumission of all slaves; a revolutionary stance at the time. While his brother’s writing was often more practical, Gregory’s tended toward the abstract, the philosophical, and the mystical—his commentaries on the Song of Songs are a masterwork of early mystical theology. Gregory was very close to his sister, Macrina, whom he considered the theological authority in their unusually holy family, going so far as to eulogize her as his teacher in an age where it was unthinkable that a woman could teach a man anything. One of his greatest works, On the Soul and Resurrection puts Macrina at the center of a Socratic-like dialogue with himself on the subject of death and the soul’s condition after death—indeed, at the time, Macrina was herself on her deathbed, and Gregory was struggling to make sense of both her imminent death and the death of their brother Basil. It is a work full of philosophical insight and influence, and grapples with some of the most mysterious questions that still confront our Christian theology today.
Major Works:Â Against Eunomius, On the Soul and Resurrection, Homilies on the Song of Songs
“That light [of the burning bush] teaches us what we must do to stand within the rays of the true light: Sandaled feet cannot ascend that height where the light of truth is seen, but the dead and earthly covering of skins, which was placed around our nature at the beginning when we were found naked because of disobedience to the divine will, must be removed from the feet of the soul. When we do this, the knowledge of the truth will result and manifest itself.”
3. The Desert Fathers & Mothers
While technically not from a single writer, you can find the wisdom of these hermit monks and nuns in a single collected volume, The Sayings of the Desert Fathers, or Apophthegmata Patrum. It includes a whole cast of eremitic characters, from St. Anthony the Great who is considered one of the first monastics in Church history, to St. Moses the Ethiopian who was a marauder-turned-monk converted when hiding out from the law in a monastery, to St. Syncletica, a nun revered far and wide for her laconic wisdom.
The Desert Fathers and Mothers flourished primarily in Egypt during the third century; St. Anthony and the strict hermits in lower Egypt, St. Pachomios’ cenobitic monasteries in upper Egypt, and St. Amoun’s semi-hermits west of the Nile. These early monastics dedicated themselves to a disciplined life of prayer and fasting, hiding from the world in order to better intercede for it. While not unknown to the West, they have long been beloved and respected by the East as paragons of the spiritual life. Their sayings emphasize humility, silence, and charity—almost everything, including prayer, is subordinate to what they refer to as “the law of love”. Even the most Spartan of their maxims, some only a mere sentence long, cut to the heart of what it means to be human–and often aren’t without a sardonic sense of humor.
Major Works: Collected in Sayings of the Desert Fathers
“Abba Lot went to see Abba Joseph and said to him, ‘Abba as far as I can I say my little office, I fast a little, I pray and meditate, I live in peace and as far as I can, I purify my thoughts. What else can I do?’ Then the old man stood up and stretched his hands towards heaven. His fingers became like ten lamps of fire and he said to him, ‘If you will, you can become all flame.'”
4. St. John of Damascus
This Syrian saint lived during a time of violent controversy in the Eastern Church. In eighth century Byzantium, a fierce debate intermittently raged over the use of icons and in worship. The iconodules supported their use, but the iconoclasts—“image-breakers”—did not believe it permissible to depict Jesus or the saints. St. John, an intellectual and priest-monk at Mar Saba monastery near Jerusalem, spoke out strongly against the iconoclasts–and paid for it. Legend has it that the iconoclast Emperor Leo III sent forged documents to the caliph of the area in which John lived implicating John in treason; the caliph responded by cutting off John’s right hand. After praying to the Theotokos, the hand was miraculously restored. In thanksgiving, he had a silver hand made and attached to her icon, which was known ever afterward as the “Tricheirousa” or “Three-Handed” icon.
His written works in support of icons became instrumental to the Second Council of Nicaea, where they helped the Council rule in favor of the iconodules. This event is celebrated on the Second Sunday of Lent in the Eastern Churches, and is known as “The Triumph of Orthodoxy.” St. John went on to write about a variety of intellectual subjects, and produced some of the first known Christian refutations of Islam in writing. His most important works deal with intersections between the material and spiritual, and the value of the material in the spiritual life.
Major works:Â Apologetics Against Those Decrying the Holy Images, The Treatises On Divine Images, An Exact Exposition of the Orthodox Faith
“Possibly a contentious unbeliever will maintain that we worshiping images in our churches are convicted of praying to lifeless idols. Far be it from us to do this. Faith makes Christians, and God, who cannot deceive, works miracles. We do not rest contented with mere colouring. With the material picture before our eyes we see the invisible God through the visible representation, and glorify Him as if present, not as a God without reality, but as a God who is the essence of being. Nor are the saints whom we glorify fictitious. They are in being, and are living with God; and their spirits being holy, the help, by the power of God, those who deserve and need their assistance.”
5. St. Isaac of Nineveh
Another Syrian saint, Isaac was a seventh century contemplative who is remembered for  his works on asceticism and mysticism. He entered the monastic life at an early age, and rigorously applied himself to the study of theology. Well respected for his wisdom, he was elevated to the bishopric of Nineveh but found himself ill-adapted to administrative duties and abdicated after only a few months to pursue life as an anchorite. His works are characterized as melancholic and mystical, with a particular emphasis on the activity of the Holy Spirit in one’s spiritual development, as well as the sick and dying. Isaac’s writings are also concerned with personal acetic struggle, and he often reiterates that outward actions and repetitions are not nearly as important as experiencing the love of God directly. He is lovingly venerated in the Eastern Churches, particularly by the Oriental Orthodox.
Major works: Few are extant, but exist in various collections like Hilarion Alfeyev’s The Spiritual World of  Isaac the Syrian.
“What is a merciful heart? It is a heart on fire for the whole of creation, for humanity, for the birds, for the animals, for demons, and for all that exists. By the recollection of them the eyes of a merciful person pour forth tears in abundance. By the strong and vehement mercy that grips such a person’s heart, and by such great compassion, the heart is humbled and one cannot bear to hear or to see any injury or slight sorrow in any in creation. For this reason, such a person offers up tearful prayer continually even for irrational beasts, for the enemies of the truth, and for those who harm her or him, that they be protected and receive mercy.”