One of the two most important fourth-century Syriac writers,1 Aphrahat is known only through the Demonstrations attributed to him, twenty-two short pieces that address various topics. Nothing about his biography is known.2 The style of the Demonstrations is instructive but often also polemical; Aphrahat poses a problem or describes someone else’s erroneous understanding of a theological point, and then offers a response supported by abundant biblical citation. In many of the Demonstrations, Aphrahat takes issue with positions he attributes to Jews, and this Demonstration is no different. Though it is not explicitly titled Against the Jews, as other pieces attributed to him are, this Demonstration is written as advice to an imagined Christian friend who seeks to answer several objections supposedly raised by Jews about how Christians speak of Jesus. Whether those objections were voiced in reality or were imagined by Aphrahat, the fact that he frames his work as a response to Jewish claims about scripture suggests that he sees as much intellectual and cultural continuity between Christianity and Judaism as he sees difference.

In 610 Sergius became patriarch of Constantinople and later the same year crowned Heraclius as emperor (r. 610–641). Sergius would remain central to imperial religious policy until his death in 638. These were tumultuous years, as the empire faced incursions from Avars to the northwest and, more threateningly, from the Persian shah Khusro II to the east. After Khusro’s initial success, including the capture of Jerusalem and the True Cross, Heraclius and his allies defeated the shah in 627 and restored the True Cross in 630. In the coming twelve years, however, the empire would lose Syria, Palestine, and Egypt to a new invader, the Arab tribes. Internally, Christians of the eastern Mediterranean were divided. In 638 Sergius penned a fateful Ekthesis or “exposition” of faith, in the hopes of ending certain disputes among Chalcedonians. The Ekthesis, issued in the name of Heraclius, repeats the prohibition initially issued in 633 in the Psēphos on teaching either a single or two activities in Christ (the positions known, respectively, as monoenergism and dyoenergism).

Opusculum 7 is another work of Maximus that stems from his involvement in the monoenergist and monothelite controversies discussed in the introduction to Ambiguum 31 to Thomas. Opusculum 7 dates to 641, and so is the latest of the texts included here. Unlike Opusculum 6, this is a lengthy and highly developed “dogmatic book,” which Maximus sent to one Marinus, a deacon. We know little about Marinus’s identity, but Maximus wrote several letters and texts to him. In Opusculum 7 Maximus defends both a fully dyothelite position and a hermeneutic for reading authoritative theological texts. As is clear from his fondness for expositing Gregory of Nazianzus, the latter argument is central. Opusculum 7 responds to the Ekthesis (638), which was the definitive statement of monothelitism, holding that in Christ there are two natures but one activity (energeia) and one will (thelēma). Against this Maximus holds that will is a capacity and process irremovable from activity, and that activity, in turn, is nature (physis) in action. Put differently, human beings share a common human nature, of which things like rational thought, deliberative choice, and self-determination constitute the activity. One of those things is will.

The two rival parties that met in Ephesus in July 431, one led by Cyril and his allies and the other by Nestorius and John of Antioch, failed to reach an accord and instead each condemned the legitimacy of the other. Emperor Theodosius II then intervened by arranging for a smaller group of representatives from each side to have a series of meetings in Chalcedon under his personal supervision. With Cyril under house arrest in Ephesus and Nestorius deposed and sent into exile, it was hoped that the two sides could achieve reconciliation. Some of the Easterners (so called because they came from the Roman diocese of Oriens or “East”), including John of Antioch himself, were willing to agree to Nestorius’s excommunication, but they continued to hold that Cyril’s Twelve Anathemas (also called the Twelve Chapters) appended to his Third Letter to Nestorius were tainted with heresy (especially Apollinarianism) and so insisted that they too had to be condemned. As these negotiations stretched into October, it became evident that a resolution would not be achieved in the short term, so Theodosius finally released all the bishops to disperse to their sees, including Cyril who had already departed for Alexandria.

In 412 Cyril became bishop of the church of Alexandria and all Egypt, succeeding his uncle Theophilus whose episcopacy was famously marked by controversy with the Constantinopolitan church in the person of its bishop, John Chrysostom. Cyril carried forward his uncle’s legacy by entering into a dispute with another bishop of Constantinople, Nestorius, within the first year of the latter’s episcopal tenure in the Eastern capital. Soon after the start of Nestorius’s episcopacy in 428, a local Christological dispute erupted between two groups in Constantinople regarding the propriety of the terms Theotokos (“bearer of God”) and Anthropotokos (“bearer of the human being”) for the Virgin Mary. Nestorius handled the situation by rejecting both terms and proposing that the word Christotokos (“bearer of Christ”) be used instead, though this solution did little to quell the conflict. In early 429 Cyril, claiming that these rumblings in the imperial capital were beginning to cause distress and uncertainty in Egypt, decided to stake out a position in the growing debate by denouncing Nestorius’s Christology in his Festal Letter 17 and Letter to the Monks of Egypt, though without naming Nestorius in either communication.

The Ascension of Isaiah imagines Isaiah’s tour of the seven heavens, the descent of Christ through the divine realms in the form of an angel, and the death of the prophet at the hands of King Hezekiah’s wicked son, Manasseh. This enigmatic work falls into two main parts: the martyrdom of Isaiah (chapters 1–5) and the vision of Isaiah (chapters 6–11). There is no consensus about the date, composition, or provenance of the Ascension of Isaiah. A 1996 monograph on the text stresses the unity of the work and locates it in the second century CE, probably in Syria.1 This all, however, remains disputed.

Timothy Aelurus was the episcopal successor in Alexandria to the luminaries Cyril (412–444) and Dioscorus (444–451). The sobriquet “Aelurus” has been variously interpreted as “the Cat” or “the Weasel,” and it was purportedly bestowed by enemies on account of his ascetical emaciation. A monk in his youth, he was ordained presbyter by Cyril and was in the entourage of Dioscorus at the second Council of Ephesus in 449. After the latter’s deposition at the Council of Chalcedon in 451, Proterius, a Chalcedonian, was installed as bishop of Alexandria. Timothy, however, remained loyal to Dioscorus. When news of Emperor Marcian’s death (on January 26, 457) reached Alexandria in early February, this sparked the anti-Chalcedonian faction to find at long last a replacement for Dioscorus. They chose Timothy, who was consecrated as a rival bishop on March 16, 457, possibly by only two bishops and thus irregularly (since three bishops were required for a canonical ordination as bishop).

The so-called Tome to the Antiochenes was penned by Athanasius of Alexandria and others in connection with the Council of Alexandria in 362. It was sent to the Christians of Antioch to help reconcile two factions there with longstanding differences and rival bishops. The first group was the “Meletians,” supporters of Meletius, who was consecrated bishop of Antioch in 361 with the support of Eudoxius, bishop of Constantinople. Meletius had had some association with the imperially backed Homoianism of the late 350s, but by 361 was seen as Homoiousian-leaning – the public expression of which views got him exiled soon after his consecration.1 The other group was the “Eustathians,” Nicene supporters of the long-dead Eustathius, who had been deposed as bishop of Antioch in 327. The leader of the Eustathians in the 360s was Paulinus, who was consecrated as bishop of Antioch by Lucifer of Cagliari in 361. Paulinus was supported by the bishop of Rome – and Athanasius himself – as the rightful bishop. Accordingly, the Tome was addressed to the Meletians, whom Athanasius viewed as once tainted by Arianism but, as Homoians leaning toward Homoiousianism, potential allies for the Nicene cause.

Under the leadership of Timothy II Aelurus (bishop of Alexandria 457–477) the anti-Chalcedonian Church solidified communally, geographically, and theologically. The condemnation and exile of his predecessor, Dioscorus, spurred Timothy to successfully rally nearly all Egyptian bishops and priests against the Chalcedonian Definition and in favor of language pertaining to the double consubstantiality of Christ. That is, Christ was both same-in-substance with God and same-in-substance with human beings. However, the rise of Timothy’s anti-Chalcedonian Church in Egypt did not faze the emperors Marcian (r. 450–457) and Leo I (r. 457–474); their respective reigns saw no attempts to reconcile. It was Emperor Zeno (r. 474–491), with the support of Bishop Acacius of Constantinople, who intended to secure a reconciliation between the imperial Chalcedonian Church and the Egyptian anti-Chalcedonian Church.

A gem of early Christian oratory, Proclus’s first homily on the Holy Virgin draws on the emerging tradition of festal homilies such as we see in Basil of Caesarea’s Homily on the Holy Birth of Christ and Gregory of Nyssa’s Homily on the Savior’s Nativity1 and addresses the crises of his day. Proclus was bishop of Cyzicus in 430 when he proclaimed this homily in the presence of his archbishop, Nestorius, who had been installed by Theodosius II on the episcopal throne in Constantinople. The occasion, it appears, was the feast of the Virgin that had recently been instituted in Constantinople for December 26. Defying Nestorius, Proclus unequivocally defends the language of Mary as Theotokos, which for him safeguards what he calls here the “coupling of natures,” divine and human, in Christ, the “incarnate God.” To name Mary’s role in effecting this union, Proclus draws on a trove of imagery at once exuberant and focused. Mary is, following the Cappadocians, the incarnation’s “workshop,” but also a bridge, a field, and a temple.

Origen of Alexandria (ca. 185–254) was a brilliant theologian who led an instructional program under the authority of Bishop Demetrius. His reputation for learning and teaching was strong throughout the eastern Mediterranean, and he frequently embarked upon philosophical speaking tours. On one such tour Origen was ordained a priest by two Palestinian bishops, a move that, when coupled with his controversial teaching about the interrelatedness of creation and the eventual apocalyptic reunification of all rational existence (God, the angels, human souls, demons, and even the devil), spurred Bishop Demetrius to publicly censure him. Rather than subject himself to Demetrius’s episcopal rebukes, Origen relocated to Caesarea Maritima in Palestine where he would continue to teach and preach in his capacity as priest. There he would remain until his death in 253 or 254, caused by injuries he sustained under torture during the Decian persecution of 251.

Opusculum 6 is another work of Maximus that stems from his involvement in the monoenergist and monothelite controversies discussed in the introduction to Ambiguum 31 to Thomas. Opusculum 6, “Concerning the statement, ‘Father, if possible, let this cup pass from me,’” dates to 640 or 641. By that time Maximus was thoroughly embroiled in combating monothelitism. This position – which maintained that Christ had only one will (thelēma) – grew out of the somewhat vaguer and perhaps more conciliatory monoenergist position. When Heraclius promulgated the Ekthesis in 638, the deliberately nebulous language of the Psēphos gave way to a more definitive statement of the singularity of Christ’s activity and will. Maximus had already objected to monoenergism, and now all the more strongly to monothelitism. He argued that the distinction of human and divine wills in Christ did not imply their opposition, and this claim is most tested in Jesus’s prayer in Gethsemane (Matthew 26:39–40).

If Christ exists in two natures, as the Council of Chalcedon proclaims, does it follow that he performed distinct classes of activities, human and divine? If you say yes, you are a “dyoenergist” (from the Greek dyo energeiai, “two activities”); if you insist that Christ performed activities of only one class, and thus answer in the negative, you are a “monoenergist” (from the Greek for “one activity”). The dyoenergist position was defended in memorable fashion in the Synodical Letter of Sophronius of Jerusalem from the year 634. To understand this letter, as well as several documents that follow in this volume, we must set the historical context and map some difficult conceptual terrain.