Biblical Theology and Gospel Proclamation
Can expository preaching be consistently evangelistic?
Preachers sometimes shy away from expositing books of the Bible because they suspect that approach is good for teaching theology to mature Christians, but bad for helping unbelievers understand the gospel.
This concern grows when pastors contemplate preaching an Old Testament book. How could a study of the life of Abraham or a series in Haggai make the gospel clear, Sunday after Sunday? Do we simply slap an evangelistic trailer onto the end of the sermon? “For our non-Christian friends here today, I’d like to end this message about Abraham’s circumcision by telling you about how you can receive the free gift of eternal life.” Cue the altar call.
There is another, more organic way to proclaim the gospel faithfully Sunday after Sunday, even from the Old Testament. It’s by employing biblical theology.
THE BIG STORY
What is biblical theology? We might define it as the study of the Bible’s overall storyline. Together, the 66 books of the Bible tell a single narrative of God’s mission to save a people and establish a kingdom for his glory through the death and resurrection of Jesus Christ. The Old Testament sets the stage for and leads us to Jesus. The Gospels reveal him and his work. The rest of the New Testament unfolds the implications of Jesus’ death and resurrection, all the way until God fully accomplishes his mission. The more we grasp this overarching plot, the more we can see how our preaching text relates to the gospel.
Preaching a passage of Scripture with an awareness of biblical theology is like having “court sense” in basketball. Good basketball players don’t just focus on dribbling the ball to the hoop. They are aware of the location of their teammates and defenders on the court as well as the flow of play. Similarly, good exposition doesn’t merely provide a running commentary on the verses at hand. It also has a court sense of what else is going on before and after the text, and how it all relates to overall progression of God’s big story.
BIBLICAL THEOLOGY IN ACTION
Let’s look at a few biblical theology strategies we might use to relate our particular passage to the main story of the Bible, the gospel story. You might think of these strategies as possible paths that take us from our text to the gospel, like optional routes on a smart phone map app that guide you from your current location to the desired destination.
1. Promise and Fulfillment
We start with the most simple and direct route to the gospel. In promise and fulfillment, the text you’re studying contains a prophecy or promise that is explicitly fulfilled in some aspect of the gospel. Promise and fulfillment is the low-hanging fruit of biblical theology: easy to see and grasp.
So if you’re preaching Micah’s prophecy about a ruler coming out of Bethlehem (Mic. 5:2), you can easily invite the congregation to turn to Matthew 2:6 to see how it is fulfilled in the birth of Jesus. Or if you do decide to exposit the life of Abraham, you should at some point connect God’s promises to bless Abraham’s offspring or “seed” (Gen. 12:7; 13:15; 17:8; 24:7) to their fulfillment in Jesus (Gal. 3:16).
In addition to giving us obvious ways to get to the gospel, promise and fulfillment also shows us how the New Testament authors interpreted the Old Testament in light of the gospel. The more we learn to read the Bible through apostles’ interpretive lenses, the better we will get to the gospel from other texts, even those without an explicit fulfillment in Jesus.
Typology is like promise and fulfillment, except rather than a verbal prophecy being fulfilled in Jesus, we see events, institutions, or persons that foreshadow Jesus and the gospel. You might think of typology as a non-verbal prophecy.
Take the temple in Jerusalem for example. It played a central role in the Old Testament as the place of God’s saving and ruling presence among his people. But it ultimately pointed forward to Jesus. Jesus shocked the crowds when he stood in the temple and said, “Destroy this sanctuary, and I will raise it up in three days” (John 2:19). They thought he meant the literal building, but “he was speaking about the sanctuary of his body” (v. 21). Like the temple, Jesus was, and is, the physical presence of God among his people to save and reign. That’s also why the apostles repeatedly identified the church, those who are in Christ, as the temple of the Spirit (e.g., 1 Cor. 3:16-17; Eph. 2:19-22; 1 Pet. 2:5).
In light of this, let’s say you’re expositing Psalm 122, which communicates the joy of going up into God’s temple in Jerusalem: “I rejoiced with those who said to me, ‘Let us go to the house of the Lord’” (v. 1). You can employ the temple typology to help people, even unchurched people, see the greater joy of going to Jesus by faith.
The New Testament is full of such types of Jesus and his work. The apostles saw Jesus as the last Adam, the true Passover lamb, the new Moses, the once-for-all sacrifice of atonement, the great high priest, the anointed king (Messiah) from David’s lineage, true Israel, and more. These well-traveled routes can faithfully take you from many places in Scripture to Jesus and his saving work.
I’m using the word “themes” to describe recurring motifs or images in the biblical storyline that don’t point directly to Jesus the way typology does. And yet these themes or motifs are integrally connected to the gospel and can help us locate our text in the unfolding biblical story.
A classic biblical theme is creation. The Bible begins with “In the beginning God created the heavens and the earth.” God brought order out of chaos, made Adam and Eve in his image, and commanded them to rule over creation and fill it with their offspring, all for God’s glory. Tragically, Adam and Eve failed their calling and rebelled against God.
But God had a plan to redeem his creation. Throughout the Old Testament we see repeated creation “reboots,” events where God graciously begins again with his people, and the new beginning is described with creation imagery and language. These creation reboots include Noah and his family after the flood, Israel’s exodus from Egypt and entrance into the promised land, Solomon’s establishment of an Edenic kingdom, and even the Israelites returning from Babylonian captivity. Yet in each of these instances the reboot failed. Humanity rebelled. Adam choked again and again. Would any of these Adamic recasts ever get it right?
Yes. The last Adam, Jesus Christ, did the will of the Father perfectly. Jesus’ resurrection and the salvation of his people launched the true new creation. And it continues to grow today. Jesus sent his saved people out to subdue the earth and fill it with sons and daughters of God through the gospel message. And someday this work will culminate in a new heavens and earth, far greater and more glorious than the original.
Can you see how being able to trace the creation motif provides a framework for organically moving from many texts to the key turning point of the new creation, the death and resurrection of Jesus?
There are many other thematic threads that weave together in the biblical storyline, like the covenants, the Exodus, the day of the Lord, and the kingdom of God.
4. Ethical Teaching
But what if you’re trying to preach through Proverbs or the Ten Commandments? What if you were really crazy and tried do expository evangelism from Leviticus? It seems those kinds of passages are better for teaching the “do’s” and “don’ts” of mature Christian living rather than showing unsaved people what Jesus has done so that they could become Christians.
Again, biblical theology maps a way from law to gospel. We can read specific moral commandments within the flow of the Bible’s storyline in at least three ways. First, the Bible’s laws and ethics lead us to Jesus by showing us our sin and need of a savior. As has often been said, God’s commandments act like a mirror to confront us with our moral deformity. As we read Israel’s history of chronic moral collapse, we see humanity’s story, and our own. “For no one will be justified in his sight by the works of the law, because the knowledge of sin comes through the law” (Rom. 3:20).
Second, the Bible’s moral commands point us to Jesus as the one who perfectly kept them. He didn’t come to destroy the law of God but to fulfill it in every way (Matt. 5:17). All of God’s other sons (Adam, Israel, Israel’s kings) were prodigals; Jesus alone pleased the Father. And so the ethical commandments of the Bible ultimately reveal the character of Jesus himself.
Third, through reliance on the power of Jesus’ resurrection and his Spirit in us, we can now keep God’s laws as obedient sons and daughters. Jesus rescued us from the power of sin “in order that the law’s requirement would be accomplished in us who do not walk according to the flesh but according to the Spirit” (Rom. 8:4).
So imagine you’re preaching Proverbs 11:17: “A kind man benefits himself, but a cruel man brings disaster on himself.” By following the contours of biblical theology you won’t merely give a 30 minute message on how to be more kind. You might also show how we fail at kindness and excel at cruelty in subtle ways. You will point people to Jesus’ embodiment of kindness, especially in giving his life for sinners. And finally, you will connect that kind grace of Jesus to ourselves as the fuel for our own transformation through the Holy Spirit.
When we begin to sense the flow of biblical theology, we will also see how the gospel often solves Old Testament puzzles. How would God fulfill his promises to David once Judah had gone into exile and there was no king in Jerusalem? If the temple sacrifices took away sin, then why did God judge Israel? The Old Testament often speaks of God’s blessings on the righteous and judgment on the wicked. So why do we see the opposite?
We could say more here, but for now suffice to say that when you encounter a biblical conundrum, consider how the gospel of Jesus might resolve the mystery. Like a great novel, the Old Testament sets up plot tensions that the hero, Jesus, resolves.
“YOU ARE HERE”
When we use biblical theology to practice this kind of gospel-conscious exposition, something exciting happens for unbelievers. Not only are they confronted by their sin, introduced to Jesus, and called to repentance and faith week after week. They also begin to locate themselves within the historical flow of God’s work. The gospel isn’t merely a metaphor or idea that they are free to use or discard if it “works for them.” Rather, the story of Jesus is a historical force rooted in the past, continuing in the present, and dominating eternity. The God who acted in the biblical world is acting in their world too, because it is the same world, the same history, the same story.