Why an issue of SBJT focused on various essays from historical theology on the Trinity? There is a sense in which that question should never be asked given that reflection on the doctrine of the Trinity is always necessary and vitally important for the life and health of the church. It is almost a truism to say that at the heart of Christian theology is our glorious triune God and to know him is life eternal, yet we must never tire of saying it. Nothing is more important than our growing in the knowledge of the true and living God. After all, he is not only worthy of our reflection, love, adoration, and obedience, but the very purpose of our existence is to know and glorify him. Every generation of the church must repeatedly return to deep theological reflection on who God is as the triune God, not to re-invent the doctrine, but to be discipled anew in the great truths of the Christian faith. In fact, if we do not get our doctrine of God right, especially the doctrine of the Trinity, it will not be too long before other areas of our theology begin to falter and crumble. Every doctrine of Christian theology ultimately finds it grounding in the great and glorious triune God of Scripture. It is always our privilege and joy to think more deeply about the Trinity and hence the reason for the subject matter of this issue of the journal.

However, there is also another reason why this issue of SBJT is devoted to the Trinity. Over the last number of years within evangelical theology there has been a growing and heated debate on some of the specifics of the doctrine. The debate had been brewing for a number of years but in the last year it came to a head in the blogosphere, in various conferences, and now in the publications of various books. The main point of contention has centered on our understanding of the person-relations between the Father, Son, and Holy Spirit in eternity (ad intra), and the relations of the divine persons in the execution of God’s plan in redemptive-history (ad extra). Specifically, the debate centered on the question of whether we should think of the divine person-relations in eternity (ad intra) in terms of authority-submission relations or not. Is it right and biblical to say that the Father, from eternity, is distinguished from the Son and Spirit because he alone has the person-property of “authority” while the Son and Spirit do not? Or is “authority” best viewed in relation to the divine nature and as an exercise of divine attributes, so that the divine persons equally share the same nature and thus authority, yet exercise authority according to who they are as Father, as Son, and as the Holy Spirit?

For some evangelicals, as represented by the label ERAS (eternal relational authority and submission), the Father is distinguished from the Son and Spirit by his eternal possession of the personal property of “authority.” The Son and Spirit, on the other hand, are distinguished from the Father by not having this personal property of authority; instead they have the personal properties of submission and procession respectively. The ERAS view contends that the way the divine persons are distinguished is not merely by eternal “relations of origin” (taxis) but also by this authority-submission ordering between the Father, Son, and Spirit from eternity (ad intra). In this way, ERAS argues for a specific kind of taxis between the divine persons from eternity that includes relations of origin (paternity, eternal generation, and eternal procession) and authority-submission relations. What occurs in the economy (ad extra), especially in regard to the submission and obedience of the incarnate Son, is true of what the Son is from eternity as the Son who submits to the Father and derives his authority from him. “Authority,” then, is not an attribute of the divine nature; instead it is a personal relationship or role that is crucial in distinguishing the divine persons.

Other evangelicals reject the ERAS view for at least two reasons. First, they argue that ERAS is not the consistent teaching of pro-Nicene orthodoxy and out of step with the tradition. Second, they argue that Scripture does not teach that there is an additional authority-submission ordering in eternity between the divine persons. Instead, the only eternal ordering (taxis) between the divine persons is the distinguishing person-properties of paternity (Father), sonship/eternal generation (Son), and eternal procession (Spirit). In other words, the only distinguishing person-properties of Father, Son, and Holy Spirit, are the “relations of origin” or “modes of subsistence” and not additional person-properties of authority-submission relationships or roles. Also, contra ERAS, this view argues that “authority” is best understood as an exercise of divine attributes tied to the divine nature which Father, Son, and Spirit share equally although they exercise authority according to their mode of subsistence, namely, the Father through the Son by the Spirit.

As noted, this trinitarian disagreement among evangelicals has led to a lot of current discussion, especially in the last year. Most recently it started on the blogs but now it is reflected in a number of recent books on the subject. When the most recent discussion began, some of it was not helpful due to the overheated rhetoric on both sides. The reason for this was partly due to the fact that the debate occurred in the blogosphere, which is not always the best place to debate serious and difficult theological issues. Yet, for the most part, the discussion has been helpful and if used rightly, it affords a wonderful opportunity to think deeply about our glorious triune God. We must never grow tired of gaining greater precision and clarity in our theological thinking, especially when it is about the God who has created and redeemed us.

Probably some of the most useful discussion has centered in the area of historical theology. In an overgeneralized way, it is fair to say that evangelical theology has been weak on historical theology, especially in regard to the Patristic and medieval eras. In much of our theological training of students, evangelical seminaries have done a wonderful job in teaching people the original languages, grounding them in biblical studies and in many areas of systematic theology. Yet, in certain doctrinal areas such as the Trinity and Christology, our grasp of historical theology has been weaker than in other areas such as the doctrine of salvation. One of the results of the recent trinitarian discussion and debates has been a renewed look at church history. It has allowed us to go back and looked anew at how the church formulated the doctrine of the Trinity in the past. By starting with Nicaea and thinking through pro-Nicene trinitarian theology, greater clarity and precision has been brought to the overall discussion.

No doubt, Scripture is our final authority and we gladly confess sola Scriptura. But as many acknowledge, the Reformation confession of sola Scriptura does not entail that Scripture is read and theology is practiced apart from the wisdom of the past. Previous confession and creeds serve as secondary standards, but they are still very important for us. This is especially the case in the doctrines of the Trinity and Christology. Why? Because from the earliest of councils to the present, there has been a consistent confession and theological formulation of the Trinity and the person of Christ. To ignore the past in these specific doctrinal areas is very unwise. Yes, we must test these statements and formulations by Scripture, but we also stand on the shoulders of those who have come before us, and given the consistent theological affirmation of these doctrines, we are wise to go back and to think anew about what our forefathers have said on these issues.

With that in mind, this issue of SBJT will not engage the current debate directly. Instead, we thought it most helpful to engage past theologians who have contributed much to our understanding of the doctrine of the Trinity as they have reflected deeply on Scripture. Given our space limitations we sought to engage with past theological giants from the beginning of the church until recent times, hence the reason for essays starting in the Patristic era, to the medieval world, the Reformation, and the nineteenth and early twentieth century. Our goal is to learn from the past in order to sharpen us in the present. Before we can engage constructively in the current debate, it is crucial to listen to the past and to learn from those who have preceded us. In that spirit, we offer this issue of SBJT on the glorious doctrine of the Trinity. It is my prayer that the current discussion and debate will lead us to a greater knowledge of who our great triune God is, how the divine persons relate to one another—not merely as an exercise in speculative theology—but for the life and health of the church. What is desperately needed today is to think big thoughts about God and wrestling with the doctrine of the Trinity is certainly the place to begin. May our glorious triune God teach us more about himself as we reflect on his Word and learn from our theological forefathers.

Read more articles on the Trinity from the latest issue of the Southern Baptist Journal of Theology.