Divine simplicity is the idea that, as the ultimate principle of the universe, God must be a non-composite unity not made up of parts or diverse attributes. The idea was appropriated by early Christian theologians from non-Christian philosophy and played a pivotal role in the development of Christian thought.
Andrew Radde-Gallwitz charts the progress of the idea of divine simplicity from the second through the fourth centuries, with particular attention to Basil of Caesarea and Gregory of Nyssa, two of the most subtle writers on this topic, both instrumental in the construction of the Trinitarian doctrine proclaimed as orthodox at the Council of Constantinople in 381. He demonstrates that divine simplicity was not a philosophical appendage awkwardly attached to the early Christian doctrine of God, but a notion that enabled Christians to articulate the consistency of God as portrayed in their scriptures.
Basil and Gregory offered a unique construal of simplicity in responding to their principal doctrinal opponent, Eunomius of Cyzicus. Challenging accepted interpretations of the Cappadocian brothers and the standard account of divine simplicity in recent philosophical literature, Radde-Gallwitz argues that Basil and Gregory's achievement in transforming ideas inherited from the non-Christian philosophy of their time has an ongoing relevance for Christian theological epistemology today.

The Cambridge Edition of Early Christian Writings provides the definitive anthology of early Christian texts, from c.100 to 650 CE. Its six volumes reflect the cultural, intellectual and linguistic diversity of early Christianity and are organized thematically on the topics of God, practice, Christ, community, reading and creation. The series expands the pool of source material to include not only Greek and Latin writings, but also Syriac and Coptic texts. Additionally, the series rejects a theologically normative view by juxtaposing texts that were important in antiquity but later deemed 'heretical', with orthodox texts. The translations are accompanied by introductions, notes, suggestions for further reading and scriptural indices. The first volume focuses on early Christian writings about God's nature and unity, and the meaning of faith. It will be an invaluable resource for students and academic researchers in early Christian studies, history of Christianity, theology, religious studies and late antique Roman history.

Gregory of Nyssa is firmly established in today's theological curriculum and is a major figure in the study of late antiquity. Students encounter him in anthologies of primary sources, in surveys of Christian history and perhaps in specialized courses on the doctrine of the Trinity, eschatology, asceticism, or the like. Gregory of Nyssa's Doctrinal Works presents a reading of the works in Gregory's corpus devoted to the dogmatic controversies of his day. Andrew Radde-Gallwitz focuses as much on Gregory the writer as on Gregory the dogmatic theologian. He sets both elements not only within the context of imperial legislation and church councils of Gregory's day, but also within their proper religious context-that is, within the temporal rhythms of ritual and sacramental practice. Gregory himself roots what we call Trinitarian theology within the church's practice of baptism. In his dogmatic treatises, where textbook accounts might lead one to expect much more on the metaphysics of substance or relation, one finds a great deal on baptismal grace; in his sermons, reflecting on the occasion of baptism tends to prompt Trinitarian questions.

Synopsis: Studying the early church can feel like entering a maze of bishops, emperors, councils, and arcane controversies. This book introduces early Christian theology by focusing on one particularly influential figure, Basil of Caesarea (ca. AD 330-378). It views Basil against the backdrop of a Roman Empire that was adopting Christianity. In Basil's day, Christians were looking for unity in the teaching and practice of their faith. This study acquaints the student with Basil's brilliant-and often neglected-theological writings. In particular, Saint Basil's reflections on the Trinity emerge from these pages as fascinating and illuminating testimonies to the faith of early Christians. Endorsements: "For decades, Basil's thought was overshadowed by the reputation of his brother, Gregory of Nyssa. But in recent years a new generation of scholarship-Volker Drecoll, Mark DelCogliano, Philip Rousseau, and Andrew Radde-Gallwtiz-has shown us anew the power of Basil as theologian . . . This concise and elegant discussion offers us the best short introduction to Basil available in any language." -Lewis Ayres, Bede Professor of Catholic Theology at Durham University "Basil of Caesarea's gifts as church politician and monastic founder have attracted much attention in recent scholarly literature, though his importance as a thinker and theologian had been neglected in favor of his younger brother, Gregory of Nyssa. In this clearly written book, Andrew Radde-Gallwitz helps us see Basil's brilliance as a theologian. Basil of Caesarea establishes Radde-Gallwitz as one of the finest scholars of Christian late antiquity." -Andrew Louth, Professor Emeritus of Patristic and Byzantine Studies at Durham University Author Biography: Andrew Radde-Gallwitz is Assistant Professor of Theology at Loyola University Chicago. He is the author of Basil of Caesarea, Gregory of Nyssa, and the Transformation of Divine Simplicity (Oxford University Press, 2009).

Basil of Caesarea is considered one of the architects of the Pro-Nicene Trinitarian doctrine adopted at the Council of Constantinople in 381, which eastern and western Christians to this day profess as ""orthodox."" Nowhere is his Trinitarian theology more clearly expressed than in his first major doctrinal work, Against Eunomius, finished in 364 or 365 CE. Responding to Eunomius, whose Apology gave renewed impetus to a tradition of starkly subordinationist Trinitarian theology that would survive for decades, Basil's Against Eunomius reflects the intense controversy raging at that time among Christians across the Mediterranean world over who God is. In this treatise, Basil attempts to articulate a theology both of God's unitary essence and of the distinctive features that characterize the Father, Son, and Holy Spirit--a distinction that some hail as the cornerstone of ""Cappadocian"" theology. In Against Eunomius, we see the clash not simply of two dogmatic positions on the doctrine of the Trinity, but of two fundamentally opposed theological methods. Basil's treatise is as much about how theology ought to be done and what human beings can and cannot know about God as it is about the exposition of Trinitarian doctrine. Thus Against Eunomius marks a turning point in the Trinitarian debates of the fourth century, for the first time addressing the methodological and epistemological differences that gave rise to theological differences. Amidst the polemical vitriol of Against Eunomius is a call to epistemological humility on the part of the theologian, a call to recognize the limitations of even the best theology. While Basil refined his theology through the course of his career, Against Eunomius remains a testament to his early theological development and a privileged window into the Trinitarian controversies of the mid-fourth century.