By and large, American evangelical Christians have conservative views of Scripture and morality. According to theologian Matthew Barrett, however, their most basic claims about God are often remarkably revisionist.

Barrett, professor at Midwestern Baptist Theological Seminary and executive editor of Credo Magazine, is the author of Simply Trinity: The Unmanipulated Father, Son, and Spirit. The book—a follow-up to his 2019 work None Greater: The Undomesticated Attributes of God—does two things. First, it shows how a good portion of evangelical theology on the Trinity has drifted from the classical Christian tradition. Second, it recruits a veritable “dream team” of teachers from across that tradition to lead readers back to the safe harbor of biblical orthodoxy. The tone is accessible, but the sources are deep.

How has evangelicalism gone wrong in its understanding of the Trinity? Barrett ranges broadly, but he fixes on the development, in recent theology, of what he calls “social trinitarianism.” Proponents of this view, which is more of a common posture than a monolithic school, tend to conceive of the oneness of God as a community of persons. Barrett introduces some of its major figures, including liberal theologians like Jürgen Moltmann and Leonardo Boff and American conservative counterparts like Wayne Grudem and Bruce Ware.

The hallmark of social Trinitarianism is its willingness to appropriate the relationships between the persons of the Trinity as a model for various social projects. For liberals like Moltmann and Boff, this can mean invoking the equal status of Father, Son, and Spirit to advance an egalitarian vision of society. Conservatives like Grudem and Ware sometimes point to supposed hierarchies within the Trinity—namely, what they call the Son’s “eternal submission” to the Father—as grounds for their complementarian views on gender roles. (Plenty of complementarians disagree. Liam Goligher, pastor of Tenth Presbyterian Church, raised the alarm several years ago in a viral blog post accusing Grudem and Ware of undermining the unity that exists between Father, Son, and Spirit.) Simply Trinity provides a thorough analysis of how revisionist trends in Trinitarian theology have settled into the seemingly conservative world of American evangelicalism.

What’s the way home? In part two of his book, Barrett retrieves classical Trinitarian teachings, addressing the relationship of eternity and history while affirming the oneness and simplicity of God. The doctrines he covers—the “eternal generation” of the Son, the “eternal procession” of the Spirit, and the “inseparable operations” of the triune God—can sound rather elevated, but Barrett explains them with ease and clarity.

Amid these chapters, Barrett also offers a single chapter examining the claim by Grudem, Ware, and others that the Son is “eternally subordinate” to the Father. He rightly shows that the relations of origin between Father, Son, and Spirit profoundly affect our understanding of salvation.

The book isn’t perfect. Barrett doesn’t always go deep enough in addressing either the root causes of recent revisionism or the glories of classical Christian understandings of the Trinity. And he fails to locate the work of Trinitarian reflection within larger questions of Christian spiritual formation, which restricts the book’s focus mainly to matters of intellectual debate and biblical interpretation.

This doesn’t quite match the mode of classical Christian thought. Take the fourth-century church father Gregory of Nazianzus, for example. In his Five Theological Orations, he certainly addresses Bible passages about the Father, Son, and Spirit—but only after reflecting on the spiritual preparation needed for Trinitarian conversation.

In his Confessions, Augustine demonstrates that God, as characterized in Scripture, is a character unlike any other. But Social Trinitarianisms, of the left or the right, tend to make the mistake of drawing false analogies between God and other people. Unless we address that root malady, we’ll continuing seeing symptoms of theological error pop up from time to time.

Still, Simply Trinity goes a long way toward identifying and excising some of these harmful tendencies. For anyone who has read confusing blog posts about the Trinity in recent years, the book will help you regain your theological bearings. And for anyone seeking to recover the riches of worshiping one God in three persons, Barrett will prove a more than able guide.

Michael Allen is the John Dyer Trimble Professor of Systematic Theology at Reformed Theological Seminary in Orlando, Florida. He is a co-editor of The Oxford Handbook of Reformed Theology.

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Simply Trinity: The Unmanipulated Father, Son, and Spirit
Our Rating
4 Stars - Excellent
Book Title
Simply Trinity: The Unmanipulated Father, Son, and Spirit
Baker Books
Release Date
March 16, 2021
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