The recent resurgence of classical Trinitarianism has borne tremendous fruit in bringing the reality of who God is to bear in the church’s ministry and proclamation. Even in confessionally Reformed circles where subscription vows have at least maintained a background fidelity to these essential doctrines, we have greatly benefitted from the reminder about how to explain these truths and that we need to get them in front of God’s people. The reminder that we need to do something, however, often comes with the question about how to do it. One contribution Emerson and Smith’s book makes is in providing basic material to show us how to orient our people to Trinitarian doctrine.

A lot of books have been released to help pastors explain Trinitarian grammar from the pulpit. As more people get familiar again with the basic premise of the Trinity and with hearing us teach about our triune God, the impulse is naturally to want the next layer of detail. After getting the Trinity in general in front of our people, one of those next layers of instruction concerns how the triune God acts toward creation. Do the Father, Son, and Spirit do different things? Can they even do different things and act apart from one another? Or do they, necessarily even, act together in all their works? Emerson and Smith’s other major contribution in this book is to provide introductory material on this next level of doctrine about how the triune God always acts together.

This doctrine of inseparable operations teaches that God’s external works are indivisible. More specifically, it means that the Father cannot act toward creation without the Son and Spirit, the Son cannot act without Father and Spirit, and the Spirit cannot act without Father and Son. Because Father, Son, and Spirit have one common will according to the common divine essence, they necessarily act together in everything that they do in every work directed outside of the divine essence.

The question might be, why this emphasis on God’s works toward creation in this doctrine of inseparable operations? The distinction here is that God’s internal works, contrasted with his external works, primarily pertain to the distinction of the persons. Internally, the Father eternally generates the Spirit, the Son eternally proceeds from the Father, and the Spirit eternally spirates from both Father and Son. Although these eternal relations of origin are not operations undertaken by each person that undermine divine simplicity, these eternal subsistences constitute the unique personal properties belonging to each person. These internal activities pertain to the distinction of the persons, but God’s external works all presume the one common divine will exercised by Father, Son, and Spirit together.

Emerson and Smith outline the biblical teaching to explain why the one God must share one will and, therefore, why Father, Son, and Spirit must act inseparably. The Father always works through the Son by the Spirit. Nevertheless, the authors explain how this truth of inseparable operations stands alongside with biblical teaching that often associates particular works with a specific divine person. This doctrine is called appropriation, wherein we can fittingly ascribe a work to one divine person so long as we know that his more pronounced relationship to that work does not preclude the other two’s involvement.

We might think here of the incarnation, which obviously has a pronounced role for the Son. Indeed, the Son alone became incarnate. Still, the Father sent the Son and the Spirit works the Son’s conception in the virgin’s womb. Although the Son alone assumed our nature, the incarnation as a divine work was still performed, in some way or other, by the Father, Son, and Spirit.

This volume traces the doctrine of inseparable operations, never neglecting to nuance this truth according to appropriations, through exploration of several key doctrines. Emerson and Smith look at revelation, providence, creation, salvation, the church’s mission, communion with God, sanctification, and judgment. For each topic, they show how it pertains to the work of the triune God inseparably, but also why we can and should speak biblically in terms of various appropriations. We do not want to downplay biblical emphases that often stress a divine work in relation to one divine person. Emerson and Smith, however, show that we also do not want to miss biblical teaching that coordinates (at times implicitly but nonetheless truly) that same work to the triune God as such.

The strength of this approach to exploring the doctrine of inseparable operations in relation to various other doctrines is that it shows how the issues that potentially might confuse us actually demonstrate this truth. For example, we might presume that the Father should alone get credit for creation. Yet, Scripture gives explicit place for the Son and Spirit in creation. The same proves true for all the doctrines this book explores.

The upshot is that the issues that might be an objection prove the point. We might think that the incarnation undermines this inseparability. But Emerson and Smith show that a fully biblical understanding of the incarnation actually demonstrates the inseparable operation of Father, Son, and Spirit in this work that is, rightly, so closely associated with one divine person. This approach to relating inseparable operations to other doctrines demonstrates that these doctrines are in fact not really challenges to inseparability, but examples of it.

This book will help laypeople find their feet in a challenging, deep doctrine. It will also help pastors get a grasp on how they might explain this doctrine to their churches and use it in ministry. I have come to appreciate more introductory books as helping me think about how to bring big, unfamiliar doctrines into my teaching at my church. This book is exemplary in showing that we can make these deepest doctrines accessible. Doctrine is, after all, for God’s people.

©Harrison Perkins. All Rights Reserved.

Matthew Y. Emerson and Brandon D. Smith, Beholding the Triune God: The Inseparable Work of Father, Son, and Spirit (IL: Crossway, 2024).

RESOURCES

• Subscribe To The Heidelblog!
• Download the HeidelApp on Apple App Store or Google Play
• Browse the Heidelshop!
• Reviews And Notices
• The Heidelblog Resource Page
• Heidelmedia Resources
• The Ecumenical Creeds
• The Reformed Confessions
• The Heidelberg Catechism
• The Heidelberg Catechism: A Historical, Theological, & Pastoral Commentary (Bellingham, WA: Lexham Press, 2025)
• Recovering the Reformed Confession (Phillipsburg: P&R Publishing, 2008)
• Why I Am A Christian
• What Must A Christian Believe?
• Heidelblog Contributors
• Support Heidelmedia: use the donate button or send a check to

Heidelberg Reformation Association
1637 E. Valley Parkway #391
Escondido CA 92027
USA
The HRA is a 501(c)(3) non-profit organization

Post authored by:

• Harrison Perkins

  

  Harrison Perkins (PhD, Queen’s University Belfast; MDiv, Westminster Seminary California) is pastor of Oakland Hills Community Church (OPC), a member of the of the Heidelberg Reformation Association, a Senior Research Fellow at the Craig Center for the Study of the Westminster Standards, associate online instructor in church history at Westminster Theological Seminary, a visiting lecturer in systematic theology at Edinburgh Theological Seminary, and author of Reformed Covenant Theology: A Systematic Introduction.

  More by Harrison Perkins ›