Here Gregory of Nazianzus fulfills his promise made at the end of his Letter 101 to Cledonius to “compose psalms, write many words, and give them meter.”1 Indeed, if Gregory’s longest argument against Apollinarius’s Christology comes in Letter 101, his most laconic one comes in these didactic verses, Poems 1.1.10–11. These texts, like Letter 101, reveal one of the most idiosyncratic features of his Christology, that Gregory takes heterodox Christologies as a personal affront; to deny that Christ had a mind, as he polemically frames Apollinarius’s position, is to deny Gregory’s mind access to salvation, and thus Gregory responded with aggressive polemic.2 This gives Gregory’s argumentation a special tenor relative to later, more technical discussions of Christology. Unfortunately, modern critical editions of Poems 1.1.10 and 1.10.11 do not exist; this translation is based on the Benedictine text contained in PG 37: 464–471.

Emperor Justinian convened the second Council of Constantinople in 553 for the sole purpose of condemning the so-called Three Chapters – the person and writings of Theodore of Mopsuestia (d. 428), certain writings of Theodoret of Cyrrhus (d. ca. 466), and the Letter to Mari the Persian attributed to Ibas of Edessa (d. 457). Why was it deemed expedient to condemn these figures and their writings a century after their deaths? The reasons are complicated and remain debated by scholars. Justinian was at least partially motivated by fostering a reconciliation of anti-Chalcedonians with the imperial, Chalcedonian church. The condemnation of the Three Chapters by a joint council of Eastern and Western bishops was probably intended to demonstrate to anti-Chalcedonians that the charge of “Nestorianism” they leveled against the imperial church was groundless.

Athanasius was bishop of Alexandria on and off for nearly fifty years, from his contested election in 328 until his death in 373. He is perhaps best known for the unflinching promotion of a theology which he claimed represented the traditional Christian viewpoints articulated at the Council of Nicaea, against Trinitarian heterodoxies he connected with Arius and those supposedly influenced by him. Various emperors irked by his ecclesio-political efforts deposed Athanasius from his see no less than five times, causing him to spend many years in exile. Though Athanasius is most famous for his defense of the Nicene doctrine of the Trinity, Christological concerns were never far from his mind and some works of his, or at least sections thereof, are even specifically Christological in focus. For example, On the Incarnation (composed ca. 328–335) is a meditation on the person of Christ and soteriology, arguing that the salvation of humanity could only be achieved through the fully divine Word becoming incarnate, whereas his Oration against the Arians 3.26–58 (early 340s) defends the reality of the incarnation of the Word against “Arian” scriptural arguments against it.

Among other things Basil of Caesarea was renowned for his preaching.1 Both as a presbyter and then a bishop, he preached on a regular basis on the various Sundays, feasts, and celebrations of the church’s liturgical calendar, as well as at synods and other ecclesiastical gatherings. Only about fifty of his homilies are extant, one of which is his Homily on the Holy Birth of Christ. Some scholars claim it is one of the earliest witnesses to the celebration of Christmas on December 25, but if not, it was probably preached on January 6 in celebration of the feast of the Theophany (also known as Epiphany). The year cannot be determined with any precision, but Basil probably delivered it during his episcopacy, 370–378, which is roughly the same period in which Letters 261 and 262 were written.

Maximus (579/80–662) is one of the most important and influential theologians of the seventh century. His numerous works delve into Trinitarian and Christological theology, metaphysics, anthropology, ascetic spirituality, and an all-embracing vision of cosmic transformation and transfiguration centred on the person of Christ. While the texts translated in this volume are primarily Christological, Maximus’s thought is not easily compartmentalized, and his reflections on the person, natures, activities, and wills of Christ are bound up with his commitment to the authority of scripture and the fathers, to philosophical rigor, and especially to salvation as deification.

In the years after the second Council of Constantinople in 553, both pro- and anti-Chalcedonians had occasionally spoken of Christ having a single activity (energeia), language which had some precedent in authors regarded as authoritative by both factions. But the validity of this so-called monoenergist doctrine was still very much a live issue on which there was no consensus in either pro- or anti-Chalcedonian circles. In the 610s, however, Sergius of Constantinople (patriarch 610–638) began to promote the doctrine of monoenergism in the name of Emperor Heraclius (r. 610–641) not only as a possible basis for reconciliation between the imperial church and miaphysite anti-Chalcedonians, but also as a legitimate clarification of Neo-Chalcedonian Christology. The apogee of imperially backed monoenergism came in 633 when on its basis Cyrus the Chalcedonian patriarch of Alexandria reached an accord with Egyptian miaphysites, an agreement memorialized in the Plerophoria, also known as the Pact of Union.

All that survives of the epistolary corpus of Apollinarius of Laodicea (ca. 315–392) are four intact letters and fragments of four others.1 What is probably the earliest Christological statement we have from Apollinarius is found in his Letter to Emperor Jovian, also called The Profession of Faith to Emperor Jovian, a letter to the new (pro-Nicene) emperor Jovian, who ascended to the throne in June 363 and ruled until his death in February 364. This letter might simply be an introductory statement of faith to a new emperor, which other bishops generally saw as unavoidable formalities to be completed without making waves. Indeed, Athanasius’s letter to Jovian (Ep. 56) simply repeated the Nicene Creed with little interpolation or interpretation. However, the fact that Apollinarius took the exercise as an opportunity to submit his Christological thought for imperial consideration might suggest a different context, perhaps that he was offering the new emperor a way forward in the efforts to reconcile the Christian factions in Antioch (Eustathians, Meletians, “Arians” of various stripes) by highlighting his own position.

Babai the Great (d. 628) was the most important author of his generation in the Church of the East (also called the East Syrian or “Nestorian” church), the largest Christian community in the Sasanian empire. A monastic reformer, hagiographer, and theologian, he championed the doctrine that came to define his church’s orthodoxy – that Christ is two natures (kyāne) and two hypostases (qnome), united in one person (parṣopā). On the Union, selections of which are translated here, was Babai’s most thorough exposition of this teaching.

The Formula of Reunion in 433 officially restored the peace of the churches but did not bring the Christological debate to an end.1 The resolution had been achieved only through delicate and difficult negotiations, and further diplomacy was required to maintain the fragile peace. The leaders of each party had the unenviable task of selling the agreement to their followers, some of whom were disinclined to accept any agreement with the opposing side. Some of the Easterners (so called because they came from the Roman diocese of Oriens or “East”), such as Theodoret, insisted that Cyril’s signing of the Formula of Reunion could only be interpreted as a departure from the position he had maintained earlier in the controversy, and they began pressing Cyril’s supporters with hard questions on this point. Cyril’s partisans then turned to the Alexandrian bishop to ask him to weigh in on the matter. On such person was Succensus, bishop of Diocaesarea in the province of Isauria, to whom Cyril penned two letters addressing the questions being posed by the Easterners and debated amongst his own followers.

The date of this text written by Apollinarius of Laodicea (ca. 315–392) is difficult to determine with specificity.1 It should simply be placed in the late 360s or 370s. Here Apollinarius demonstrates the union between divinity and flesh in Christ. He employs the Greek term hypostasis to express the basic union between Christ’s flesh and divinity. Perhaps more radically than he does in On the Body’s Union with the Divinity in Christ,2 Apollinarius now applies “same-in-substance” (homoousios) to Christ’s flesh. This text, once attributed falsely to Julian of Rome, does not fully survive in Greek.

Emperor Justinian reigned from 527 to 565, but had already played a decisive role in the reign of his uncle and predecessor Justin I (r. 518–527). Before Justin, imperial policy in Christological matters was officially dictated by the Henotikon that had been issued in 482 to reconcile pro- and anti-Chalcedonian factions within the church. Written by the patriarch Acacius of Constantinople and promulgated by Emperor Zeno, this document embraced a studied ambiguity by avoiding technical terminology in minimalist Christological formulations, by giving approval to both aspects of Cyril’s theology (represented by the strongly miaphysite Twelve Chapters and the dyophysite-leaning Letter of Reunion to John of Antioch), and by reducing the council’s work to the condemnation of Nestorius and Eutyches in order to undermine the achievement of the Chalcedonian Definition. Western bishops, who held Chalcedon in high regard, rejected the Henotikon outright, leading the bishop of Rome to break off communion with Acacius, resulting in the so-called Acacian Schism.

The Odes of Solomon consist of forty-two short poems. Their provenance, date, and original language are all disputed. At least some of the Odes must have been written before the third century since Ode 11 is found in Greek in Papyrus Bodmer XI, which is datable to the third century, and since Lactantius (ca. 240–ca. 320) includes a quotation of Ode 19 in Latin translation in his Divinarum Institutionum (IV.xii.3). Parts of five odes (1.1–5, 5.1–11, 6.8–18, 22.1–12, and 25.1–12) are also found in Coptic translation in the Pistis Sophia, which is preserved in a single Coptic manuscript, probably from the fourth or fifth century, though scholars think the Pistis Sophia itself goes back to the third or fourth century. The Syriac tradition preserves the most complete witness to the Odes of Solomon, albeit in later manuscripts: Odes 17–42 are extant in a Syriac manuscript datable to the tenth century, and Odes 3–42 in a Syriac manuscript datable to the fifteenth to seventeenth century.

Little is known with certainty about the life of Tertullian, who authored some of the very earliest Christian literature written in Latin. He was from the city of Carthage in Roman North Africa, and his literary career in this city spanned from roughly 196 to 212; he was perhaps born around 170. From the few scattered comments he made about his own life, we learn that he was raised as a pagan, and became a Christian under unknown circumstances. Most scholars now doubt other details about Tertullian’s life which come from later sources, such as Jerome’s belief that his father was a Roman centurion, and Eusebius’s suggestion that he was a lawyer in his pre-Christian career. One further point from Jerome about Tertullian’s life likewise requires cautious treatment. This is the claim that Tertullian in middle age “lapsed” away from the catholic church into Montanism, a revivalist movement of Christianity established in the second century and eventually branded as heretical.1 Though Tertullian’s later works do show increasing signs of Montanism, it is impossible to divide up his career neatly into catholic and Montanist phases, as previous generations of scholars tended to do.

Ignatius, bishop of Antioch in Syria, penned seven letters while being escorted under guard to Rome for execution during the reign of Trajan (98–117 CE). No explicit evidence confirms that he reached the imperial capital, but there is no reason to doubt the tradition that he was martyred there. These letters illuminate numerous aspects of early Christian life and thought, providing as well insight into their author’s concerns. Since the seventeenth century these letters have been included in the collection of early Christian writings known as the Apostolic Fathers. Three matters above all repeatedly surface in these letters: (1) Ignatius’s struggle against those whose teaching differed from his own; (2) his pleas for the unity of the church by communion with and obedience to the bishop; and (3) his own suffering and impending death and their meaning, which he interprets in Christological categories.

Diodore of Tarsus was an influential Christian teacher and writer about whom we know very little. Born in Antioch at some point in the early fourth century, he was trained first in theology by Silvanus (later bishop of Tarsus) and then in traditional writing and interpretation techniques in Athens. Upon his return to Antioch, Diodore became an interpreter of scripture and a teacher of interpretation in the Christian community of his native city, and, along with his friend Flavian, he embraced the ascetical life. Both Diodore and Flavian were ordained presbyters in Antioch by Meletius in the early 360s, indicating their pro-Nicene sympathies in the fractured church of that city. In the years 362–363 Emperor Julian encountered Diodore in Antioch and ridiculed him in a letter (Ep. 55). Ancient historians also report that Diodore and another man, Carterius, headed an institution where other Christians studied; it has frequently been called a “monastery” by historians, but it is perhaps more descriptive to call it a school, as reading and learning seem to have been the primary activities. Among its students were both Theodore of Mopsuestia1 and John Chrysostom, themselves influential thinkers in late ancient Christian culture.

The Ekthesis had made monothelitism imperial orthodoxy in 638 and remained in force under Constans II, who assumed the throne in 641. While this doctrine was apparently popular in some regions, it faced stern opposition from North Africa, whither Maximus and his companions had fled and whence they mounted a dyothelite insurgency. Anti-imperial fervor even inspired the North African exarch Gregory in 646/7 to proclaim himself emperor against Constans II. Faced with this emergency, in 647/8 Paul, the patriarch of Constantinople, in the name of Constans II, published a compromise document known as the Typos, which in this context means something like “general instruction.” This document replaced the Ekthesis that had previously hung in the narthex of the Great Church. The Typos forbade all discussion of Christ’s activities and wills, aiming to set the clock back to the time of the fifth ecumenical council (553). However, a synod the following year (649) at the Lateran in Rome rejected both the Typos and the Ekthesis, which led to a major clash between imperial forces, on one side, and Martin of Rome, Maximus the Confessor, and their allies, on the other.

Eusebius of Dorylaeum was a fifth-century bishop and a prominent theologian. Trained in legal practice, he became a distinguished rhetorician in Constantinople. His significant erudition earned him esteem at the imperial court. While still a layperson, Eusebius became the first person to contest Nestorius, the newly installed archbishop of Constantinople, in order to defend the title Theotokos for the Virgin Mary. When Nestorius challenged the theological propriety of the title, Eusebius confronted him in church. Cyril of Alexandria recounted the incident as follows:

John of Damascus wrote two polemical works against the East Syrians, whom he differentiated from the West Syrians as “Nestorian.” The West Syrians, who rejected the Council of Chalcedon (451), conflated John’s pro-Chalcedonian position with that of the East Syrians, and thus referred to both those condemned at the Council of Ephesus (431) and those who accepted Chalcedon as “Nestorian.” John’s argument here is primarily focused on contradicting the East Syrians, but he seems also to be differentiating his party from theirs, having the more prevalent and powerful West Syrians in view. The argument of the longer of these two polemics, Against the Nestorians (CPG 8053), is centered on scripture and patristic authority; whereas that of the shorter, On the Faith against the Nestorians (CPG 8054), is more theological, although it does employ scripture (in certain sections) to a greater extent than his On Composite Nature against the Leaderless (CPG 8051).

The first eight chapters of Irenaeus’s Against Heresies (1.1–8) contain the oldest surviving account of Valentinian Gnosticism.1 No account has influenced ancient and modern understandings of Valentinian Gnosticism more than this one. Irenaeus, however, does not here relate Valentinus’s own thought. He provides, rather, a theological account circulating amongst Valentinians near the Rhône who considered themselves followers of the influential Valentinian named Ptolemaeus (Ptolemy).2 Irenaeus states (Against Heresies 1.pref.2) that his account draws upon conversations held with these Ptolemaic Valentinians as well as written sources obtained from them. But the particular author of these written sources and the relative importance of these writings to this group of Valentinians remains unknown.