Robert Letham, The Holy Trinity: In Scripture, History, Theology, and Worship (P&R Publishing, 2004).
In the Preface, Robert Letham confesses that although interacting and dealing with a wide spectrum of theologians, “from East and West, from Roman Catholicism as well as Protestantism,” this book “is written from a Reformed perspective” (ix). It should come as no surprise for a book on the Holy Trinity to be written from a Reformed perspective, it is, after all, well documented that John Calvin broke from the “Western” theological mold in his writings when he emphasized the persons of the Trinity instead of the traditional/Augustinian emphasis which highlighted “divine essence.” Letham notes that it is “tragic” that Reformed folk have failed to flourish and follow Calvin’s lead. Calvin leaned into the doctrine of the Trinity, and Letham would like to see more Calvinists leaning together with and like Calvin; Letham would like to see more Calvinists share Calvin’s Trinitarian posture. (Calvin was true to his Western/Augustinian tradition, but he did so with an openness to the Eastern/Greek emphasis. Letham says Calvin preserved the theological deposit handed to him–he conserved it–yet he contributed to its flourishing through maintaining a type of kinship through grafting in Eastern/Greek sensibilities.)
In order to consciously share the same type of posture towards the doctrine of the Trinity we must understand both the doctrine of the Trinity and its historical development (flow through different contexts). “To think clearly about the Trinity, we must grapple with the history of discussion in the church” (2).
The history of discussion in the church has centered around what are considered errors of traditional emphasis in the doctrine of the Trinity: the West is criticized for overemphasizing the “divine essence” and of slipping into modalism, and the East is criticized for overemphasizing the persons and slipping into subordinationism of the Son and Holy Spirit to the Father. But these aren’t just apparent errors. There is more tooth to them than mere conjecture . . . particularly in the West, Letham says:
Today most Western Christians are practical modalists. The usual way of referring to God is “God” or, particularly at the popular level, “the Lord.” It is worth contrasting this with Gregory Nazianzen, the great Cappadocian of the fourth century, who spoke of “my Trinity,” saying, “When I say ‘God,’ I mean Father, Son, and Holy Spirit.” This practical modalism goes tandem with a general lack of understanding of the historic doctrine of the Trinity (6).
Letham suggests that the remedy for these errors is an all out, full recovery of the doctrine of the Trinity which follows the trajectory set by Calvin. This recovery, however, is not a remedy administered “top-down” from the Ivory Towers. It is a grassroot solution. The remedial flow begins in the pew and the pulpit. Per Letham:
It is my belief that a recovery of the Trinity at the ground level, the level of the ordinary minister and believer, will help revitalize the life of the church and, in turn, its witness in the world (7).
Letham’s aim is pastoral: “Let us persevere, then, through the chapters that follow . . . for the great and and wonderful prize of knowing our triune God better” (12). I believe he accomplishes that aim in this book: Letham, in order to lead us further up and further in communion with and love for (and participation in the love and glory of) the Holy Trinity, competently leads believers from the Biblical foundations, along the historical developments, and into the modern discussions and critical issues of the doctrine of the Trinity. A recovery of the doctrine of the Trinity aids the church in fulfilling her mission because the “Trinity provides the sole basis for the greatest of human tasks,” which is to love one another. Letham notes that Scripture, specifically the Gospel of John, emphasizes again and again the “priority of love.” The church needs love in order to do her job. “The mission of the church to spread the gospel also requires the practice of love, of self-effacement, of looking to the interests of others” (478). The Trinity is the not only the model but the source of this love.