What does the plural form of the word “seed” (zera) in Genesis 12:7 have to do with justification by faith? What does a solitary figure like Melchizedek in Genesis 14 have to do with the person and work of Christ? And what about a bronze snake hung on pole in the middle of the desert—does this have any significance beyond Numbers 21?
To all these questions and more, we can answer: “Hold on! Keep reading the Bible, and you will see in good time!”
For Paul hangs his argument for justification by grace on the fact that Jesus Christ is the long-awaited offspring (literally, “seed”!), not “offsprings” (Gal. 3:16). Likewise, Hebrews centers an entire sermon on the way Christ is a priest after the order of Melchizedek. And John, following Jesus, explains how the cross of Christ saves a people snake-bit by sin: “And as Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up, that whoever believes in him may have eternal life” (John 3:14–15).
In short, the Bible, when allowed to speak on its own terms, is its own best interpreter. Biblical theology, by extension, is the discipline of letting Scripture interpret Scripture and reading the whole Bible according to its own literary structures and unfolding covenants. To put it woodenly, biblical theology seeks to read the Bible “with the grain” of God’s progressive revelation. Or to put it more academically, biblical theology is “principally concerned with the overall theological message of the whole Bible.”
It seeks to understand the parts in relation to the whole and, to achieve this, it must work with the mutual interaction of the literary, historical, and theological dimensions of the various corpora, and with the interrelationships of these within the whole canon of Scripture.[1]
1. Brian Rosner, “Biblical Theology,” in New Dictionary of Biblical Theology, ed. T. Desmond Alexander, Brian S. Rosner, D.A. Carson, Graeme Goldsworthy (Downers Grove, IL: Intervarsity Press, 2000), 3.
In short, biblical theology is not just theology that comes from the Bible. It is more specific. As Brian Rosner puts it, biblical theology is a method of reading Scripture that “seeks to analyze and synthesize the Bible’s teaching about God and his relations to the world on its own terms, maintaining sight of the Bible’s overarching narrative and Christocentric focus.”[2] And for those who are interested in pursuing biblical theology, you are in luck. The twenty-first century has produced a cornucopia of canonical resources. From the New Dictionary in Biblical Theology[3], to the New Studies in Biblical Theology series, to the recent Commentary on the New Testament Use of the Old Testament[4] and its complementary dictionary[5], to the mountain of Biblical Theologies by Graeme Goldsworthy,[6] Thomas Schreiner,[7] Jim Hamilton,[8] G. K. Beale (technically a New Testament Biblical Theology),[9] to the granddaddy of them all, Biblical Theology by Geerhardus Vos,[10] you have countless resources.
2. Rosner, “Biblical Theology,” 10.
3. T. Desmond Alexander, D.A. Carson, Graeme Goldsworthy, Brian Rosner. New Dictionary of Biblical Theology (Downers Grove, IL: Intervarsity Press, 2000).
4. G.K. Beale and D.A. Carson. Commentary on the New Testament Use of the Old Testament. (Grand Rapids, MI: Baker Academic, 2008).
5. G.K. Beale, D.A. Carson, Benjamin L. Gladd, and Andrew David Naselli. Dictionary of the New Testament Use of the Old Testament. (Grand Rapids, MI: Baker Academic, 2023).
6. Graeme Goldsworthy. According to Plan: The Unfolding Revelation of God in the Bible. (Downers Grove, IL: Intervarsity Press Academic, 2002).
7. Thomas R. Schreiner. The King in His Beauty: A Bibilical Theology of Old and New Testaments. (Grand Rapids, MI: Baker Academic, 2013).
8. James M. Hamilton Jr. God’s Glory in Salvation Through Judgment: A Biblical Theology. (Wheaton, IL: Crossway. 2010).
9. G.K. Beale. A New Testament Biblical Theology: The Unfolding of the Old Testament in the New. (Grand Rapids, MI: Baker Academic, 2011).
10. Geerhardus Vos. Biblical Theology 3rd ed. (Carlisle, PA: Banner of Truth Trust, 2014).
And wonderfully, the treasure of these of volumes, has also enriched systematic theology. As Steve Wellum’s Systematic Theology[11] demonstrates, the use of biblical theology is not only unavoidable, but necessary for doing systematic theology well. And that is the point of this essay.
While other articles have been written to define biblical theology and its use in the church, this essay aims to show how biblical theology makes systematic theology more or less biblical. That is to say, if a systematic doctrine (e.g., Christology, soteriology, or eschatology) is going to be biblical, it must incorporate and apply all the biblical data. Yet, a biblical theology of the Holy Spirit must do more than tabulate all the passages that talk about the Spirit; it must also order those passages according to the unfolding revelation of God’s plan of redemption. Positively, this means that the best systematic theologies will stand upon the best biblical theology. And negatively, this means that a poor biblical theology will result in a truncated, misshapen, or distorted doctrine.
To put it colorfully, the relationship of biblical theology to systematic theology can be called the “Butterfly Effect.”
The Butterfly Effect of Biblical Theology
In 1972, Edward Lorenz, an MIT professor of mathematics and meteorology, published an academic paper titled “Predictability: Does the Flap of a Butterfly’s Wings in Brazil Set Off a Tornado in Texas?” Lorenz explains how the smallest disturbances in the atmosphere (the flap of a butterfly’s wings) can, compounded over time, contribute to larger events in nature (a tornado). More specifically, he offers two propositions:
11. Stephen J. Wellum. Systematic Theology, Volume 1: From Canon to Concept (Nashville, TN: B&H Academic, 2024).
1. If a single flap of a butterfly’s wing can be instrumental in generating a tornado, so also can all the previous and subsequent flaps of its wings, as can the flaps of the wings of millions of other butterflies, not to mention the activities of innumerable more powerful creatures, including our own species.
2. If the flap of a butterfly’s wings can be instrumental in generating a tornado, it can equally well be instrumental in preventing a tornado.
This is the Butterfly Effect. In his theory, Lorenz is seeking to explain patterns in weather. And, for what it is worth, his work “laid the foundation for a branch of mathematics known as chaos theory, the idea of trying to predict the behavior of systems that are inherently unpredictable.”[12] For our purposes, I am applying his theory to the way small exegetical decisions in biblical theology have large ramifications in systematic theology.[13] In other words, when transposing theology from canon to concept, we should beware of the ways our biblical theology informs our systematic theology.
12. How Stuff Works, “What is the Butterfly Effect and How Do We Misunderstand It?”.
13. For philosophical purists who are less enthused about meteorology, the Butterfly Effect makes the same point Thomas Aquinas did in his On Being and Essence: “a small error in the beginning grows enormous at the end.” Credit to Brad Green who alerted me to this quotation.
This was a principle I learned from Steve Wellum when I took my first class with him in 2007. In his Issues in Biblical and Systematic Theology lectures, he discussed the ways in which various biblical systems (e.g., covenant theology, dispensationalism, progressive covenantalism, etc.) inform theological systems (i.e., systematic theology). Since then, Steve has expanded his class notes, outlining them in Kingdom through Covenant and now in his new Systematic Theology. But the point remains: small exegetical decisions impact biblical theology, which in turn shapes systematic theology. And more, if various exegetical decisions are embedded within church traditions (or denominations), then biblical theology is reinforced by historical theology and quickly hardens in theological systems and particular doctrines that have larger impact.
That is the theological application of the butterfly effect. And I want to offer a few specific examples to illustrate how this works. But first, let me suggest that a proper understanding of the Butterfly Effect, used for the purposes of systematic theology, does not promise the right conclusion. It only helps the theologian to see where theological divisions arise and how material doctrines are developed. In other words, the value of this theory is that it reminds us that doctrinal propositions are downstream from biblical interpretations. And often, when a certain interpretation is seen early on in biblical theology, it becomes easier to see why a given doctrine is affirmed or denied in systematic theology.
But enough theory. Let’s see how this works in practice.
A Wave, A Storm, and a Tornado: Three Theological Illustrations
First, the waves that batter the shores of baptism can be helped by the Butterfly Effect.
If we want to know where the headwaters of the baptism debate lie, then we need to start with the first baptism in the Bible, which comes in the flood waters of Genesis 6–8. As Peter identifies baptism with Noah and his ark (1 Pet. 3:20–21), it is vital to understand the typology of this event before making later claims for baptism. Likewise, any faithful doctrine of baptism will need to do more than define the Greek word baptizō. It will be important to follow the waters of baptism from Noah (Genesis 6–8), to Moses (Exodus 2), to Israel (Exodus 14), to Joshua (Joshua 5), to Elijah and Elisha (1 Kings 19), to Jonah (Jonah 1–2), to Jesus (Matthew 3), to the disciples (Matthew 28), and then the church in Acts.
Along the way, exegetical decisions will be made, and when they are, it will become more apparent as to how that decision impacts later systematic conclusions. Certainly, we can read our theology back onto the biblical text. But equally, when we discern one’s biblical theology—either our own or someone else’s—it becomes more plain why a theological commitment is made. For instance, J.V. Fesko and Stephen Wellum both appeal to biblical theology to argue for their alternate views of baptism, but because they make different exegetical decisions related to covenants, typology, and fulfillment, their doctrinal conclusions are also different.[14] This is an instance of the Butterfly Effect of Biblical Theology, and the earlier we can discern differences in biblical theology, the more clearly we will understand the doctrinal differences.[15]
14. J.V. Fesko, Word, Water, and Spirit: A Reformed Perspective on Baptism (Grand Rapids: Reformed Heritage, 2021); “Baptism and the Relationship Between the Covenants,” in Believer’s Baptism: Sign of the New Covenant in Christ, eds. Thomas R. Schreiner and Shawn D. Wright, NAC Studies in Bible & Theology, ed. E. Ray Clendenen (Nashville: B&H Academic, 2006), 97–16.
15. This point also applies with respect to the covenantal systems of Reformed paedobaptists and Reforemd Baptists. Both have a covenantal theology, but as the Westminster Confession of Faith (1647) and the London Baptist Confession (1689) demonstrate, differences in covenant theology relate to differing views of the sacraments.
Second, the storm that swirls around the intent/extent of the atonement is served by the Butterfly Effect.
Currently, I am working on a book on definite atonement. And after surveying the ways theologians have answered the question, “For whom did Christ die?,” my first constructive chapter traces the two seeds—the seed of the woman and the seed of the serpent. Starting in Genesis 3:15, I argue that God has always intended to save the seed of the woman (his people) from the seed of the serpent (not his people). This begins in Genesis 4, when Cain kills Abel. And it continues in that chapter, as the offspring of Cain and Seth become two types of people—the former following the ways of Cain and inviting God’s judgment by their sin; the latter calling upon the name of the Lord (Gen. 4:26) and finding salvation by faith in God. By itself this argument does not prove definite atonement, but it sets in place a biblical theological trajectory that results in a defense of definite atonement.
To identify the coordinates of my argument then, I am letting the division of humanity, the one pronounced in Genesis 3:15, to set the terms for the way I am reading Scripture. I believe this division is developed in Genesis 4, continued in Noah’s offspring, reinforced in Abraham’s offspring, and later explained by Paul in Romans 9. But, if it can be proven that Genesis 3:15 does not set a division in humanity, then it severely undercuts my argument. Disproving this exegetical point might not overturn the doctrine of definite atonement, for there are other viable arguments. But then again, it might. If Genesis 3:15 does not form a dividing line that runs through the whole Bible, the systematic argument that relies on this biblical theological argument is in jeopardy.
This is the Butterfly Effect, where small exegetical decisions inform larger biblical theological commitments which will have wide-reaching systematic implications. Practically, this means it is vitally important to begin with sound exegesis and reliable first principles. For without a solid beginning, what comes later will be built on gravel, not granite. Or to turn it around, if we are looking at the edifice of a certain doctrine, awareness of the Butterfly Effect would lead us to go back to ascertain the initial presuppositions. From those presuppositions, we can learn a great deal about where those early decisions will lead.
Third, the tornado surrounding Christian Nationalism can be helped by applying the Butterfly Effect.
To highlight one specific interlocutor, Stephen Wolfe has made a “case for Christian Nationalism,”[16] and one of his key points is that grace restores nature. This is true as far as it goes, but it leaves open the question: What is nature? Or more specifically, what can we know about the world before the fall? Brad Green has done extensive work engaging with Wolfe’s nature-grace, and I am not bringing this up to re-engage the debate. I simply want to highlight one line of thought.
16. Stephen Wolfe. The Case for Christian Nationalism. (Moscow, ID: Canon Press, 2022).
When Wolfe argues that the formation of nations precedes the fall, he is making a claim for nature that others will dispute. Personally, I would place the formations of nations in Genesis 10–11. Nations, as they are defined in Scripture, are something tied to God’s judgment of the world, especially as it relates to the formation of languages (Genesis 11) and the assignment of nations to demonic powers (Deut. 32:8–9). Certainly, in an unfallen world, families would grow into clans, clans into states, and states into kingdoms. But such kingdoms would all be of the same unfallen family and would function very differently than the nations we know today.
Long story short, if Wolfe and others have differing views on nature (i.e., the order of unfallen creation), then even if they agree on the point that grace restores nature, they will continue to be at odds with one another. Ironically, they will be using the same language, but not able to build anything together. Babel strikes again!
It remains necessary, therefore, to see how the opening chapters of Genesis introduce the subject of nations. It is not enough to appeal to one’s preferred tradition. Instead, if we are going to do “Theology by the Book,” we must return to the Bible and ask: What does Scripture say?[17] And then we must see how small interpretive decisions early on—and this could include a decision to ignore biblical exegesis—result in divergent positions on biblical theology, systematic theology, and political theology.[18]
17. While Wolfe does not make the exegetical case for nations to emerge before the fall, James Jordan does in his Christendom and Nations (Birmingham, AL: Theopolis, 2019). Accordingly, Jordan’s exegetical work would need to be compared to others who place nations as emerging post-fall at the time of Babel.
18. In Wolfe’s case, he is doing “political theory” not political theology, but the burden remains. Those who are compelled by the Bible will want to know if his theory, or anyone’s political theory, coheres with Scripture.
Using The Butterfly Effect Effectively
To reiterate my earlier point, the Butterfly Effect can be useful for understanding arguments and seeing where they go wrong (or right). But observing how small exegetical decisions can lead to large-scale theological ramifications does not guarantee that we all come to the same conclusion—or, the right conclusion. What it does promise is that those who are making arguments for theological doctrines can observe the ways that biblical theology makes systematic theology more or less biblical.
To change metaphors, when our foundation is sound, we are more likely to stand on level ground ten floors up. But when we discover a small deviation on the ground floor, it is likely that it will be more pronounced the farther up we go. Retrospectively, when we find errant doctrines, we should be able to go back and discern where the argument went wrong. Likewise, prospectively, if we find a small error at the beginning of a doctrine (e.g., the denial of an historic Adam), it will often be followed by other later errors of greater magnitude (e.g., a compromised position on inerrancy).
As it works out in time, such theological shockwaves may not be seen immediately. They may take years to develop. Equally, confessional boundaries may prevent various teachers from exercising rigorous consistency. For instance, Roger Nicole was a staunch defender of penal substitution and egalitarianism. In my estimation, the hermeneutical commitments that lead to the latter do not match the former. Yet, this is an example of blessed inconsistency—at least when it comes to the cross. And in truth, such methodological inconsistencies will show up in all theologians.
Nevertheless, for those who aim to be consistent and to work out their systematic theology from a rigorous biblical theology, the Butterfly Effect will be in full force. Small exegetical decisions in biblical theology will result in much larger theological conclusions. Accordingly, we should pay close attention our doctrine and to those teaching us theology, for if there is a small deviation in one place, it may indicate weakness in the whole system.
For truly, systematic theology that is based upon biblical theology will follow a system. And the more that we can have eyes open to see that system, the more the whole enterprise of doing theology moves from chaos to the ruling principle of Christ. For in him, all things in heaven and earth hold together, and we should aim to pursue a thorough biblical theology so that it becomes the foundation for a solid systematic theology.
Indeed, your biblical theology will make your systematic theology either more or less biblical. And it depends largely on whether small exegetical decisions follow the grain of Scripture or work against it. And so, knowing that truth, let us strive to pursue a biblical theology that coheres to all Scripture so that our systematic theology might do the same.
