The Church in God's Eternal Plan

Introduction: Before the Foundation of the World

Most people think of the church as something that began in history—at Pentecost, with Abraham, or perhaps with Adam. And in one sense, that is true. The church has a historical origin. But the New Testament makes a far more staggering claim: the church was in God's mind and purpose before history began. The church is not God's reaction to human sin; it is His eternal intention.

This passage is breathtaking in its scope. Before a single star was formed, before the first atom existed, God had already chosen a people for Himself. The church was not an afterthought, not a contingency plan, not a parenthetical insertion into God's dealings with Israel. The church—the gathered, redeemed, adopted people of God—was the purpose for which creation itself was made. As Paul will argue in Ephesians, the church is the theater in which God displays the full riches of His wisdom, grace, and glory.

In this lesson, we will trace the New Testament's teaching on the church's place in God's eternal plan, focusing especially on Paul's letter to the Ephesians, which is the highest and most developed ecclesiology in Scripture.

Election and the Church

The doctrine of election is most often discussed in terms of individual salvation: God chose particular sinners to be saved before the foundation of the world. This is true and important. But Ephesians 1 reveals that election has a corporate dimension as well. God did not merely choose isolated individuals; He chose a people. The "us" in "he chose us" is not a collection of disconnected persons who happen to be saved separately. It is a community—the church—chosen together, in Christ, for a shared destiny.

This corporate dimension of election was not new with Paul. God's election in the Old Testament was fundamentally corporate: He chose Israel as a nation (Deuteronomy 7:6–8), not merely individual Israelites. He chose Abraham in order to form a people through him. The individual was always elected into a community, never in isolation from it. Paul extends this pattern to the church: believers are chosen in Christ and thereby incorporated into His body.

Chosen "In Him"

The phrase "in him" (or "in Christ") appears eleven times in Ephesians 1:3–14. This is not incidental. The church's election is not arbitrary or abstract; it is in Christ. The Father chose a people, and He chose them in the Son. Christ is not merely the agent of salvation—He is the sphere of election. To be chosen by God is to be chosen in Christ, and to be in Christ is to be in His body, the church.

This has a crucial implication: there is no relationship with Christ that is separable from relationship with His church. Union with Christ and membership in His body are not two separate realities; they are two aspects of one reality. Calvin put it simply: "He who has God for his Father has the church for his mother."

The Mystery Revealed

One of Paul's most distinctive contributions to ecclesiology is his teaching on the mystery (Greek: mystērion). In Paul's usage, a "mystery" is not something mysterious in the modern sense—puzzling or unknowable. Rather, it is a truth that was hidden in God's plan and has now been revealed through the gospel. The mystery is an open secret—formerly concealed, now disclosed.

What is this mystery? Paul defines it with particular clarity in Ephesians 3:

The mystery, in its fullest expression, is the church itself— specifically, the union of Jew and Gentile in one body through Christ. The Old Testament hinted at Gentile inclusion (Isaiah 49:6; Ruth; Jonah), but the full scope of God's plan—that the dividing wall of hostility would be demolished and that Jew and Gentile would become one new humanity in Christ (Ephesians 2:14–15)—was not fully understood until the apostolic era. The church is not merely a practical arrangement for believers to gather; it is the grand unveiling of God's eternal purpose.

The Church as Cosmic Display

Perhaps the most astonishing statement about the church's significance comes in Ephesians 3:10:

Read that again carefully. The church is the means by which God displays His wisdom to the angelic realm—to "rulers and authorities in the heavenly places." The church is not merely a gathering of saved individuals trying to make it to heaven. It is a cosmic demonstration of God's multifaceted wisdom. When angels and demons look at the church—this ragtag assembly of former enemies now reconciled in Christ, Jews and Gentiles worshiping side by side, sinners washed clean by grace—they see the wisdom of God on display.

This elevates ecclesiology to the highest possible plane. The church is not a secondary concern for Christians who have "more important" theological interests. The church is the arena in which the most important thing in the universe is happening: the demonstration of God's glory. To diminish the church, to treat it as optional or disposable, is to miss the very purpose of God's eternal plan.

The Church and God's Glory

Paul concludes his great ecclesiological prayer in Ephesians 3 with a doxology that ties the church permanently to the glory of God:

Glory to God in the church. Not merely in creation, not merely in individual hearts, but in the church—the community of the redeemed. The church is where God's glory is made visible on earth. It is the place where His grace is embodied, His love is demonstrated, His wisdom is displayed, and His name is praised. For all eternity, "throughout all generations, forever and ever," the church will be the theater of God's glory.

The Church in Redemptive History

The church occupies a unique position in redemptive history— the unfolding story of God's saving work from creation to consummation. The Reformed tradition has helpfully articulated this through the concept of progressive revelation: God reveals His plan gradually, in stages, with each stage building on what came before and pointing toward what is yet to come.

In this framework, the church is both continuous with what came before (the covenant community stretching back to Abraham, as we saw in the previous lesson) and new in significant ways. The church lives in the era between Christ's first and second comings—what theologians call the "already/not yet" of the kingdom. The kingdom has been inaugurated by Christ's death and resurrection, but it has not yet been consummated at His return. The church exists in this tension, tasting the powers of the age to come while still groaning with all creation for the final redemption (Romans 8:23).

This "already/not yet" framework explains much about the church's experience. Why is the church both glorious and broken? Because the kingdom has come but is not yet fully here. Why does the church experience both power and weakness? Because the Spirit has been poured out but the resurrection of the body awaits. Why does the church struggle with sin even as it grows in holiness? Because we live between the cross and the consummation. The church is a pilgrim people—redeemed but not yet glorified, victorious but still fighting, certain of the destination but not yet home.

Union with Christ: The Foundation of the Church

At the deepest theological level, the church exists because of union with Christ. This is the doctrine that John Calvin called "the central doctrine of the Christian faith"—the teaching that believers are spiritually and really united to the risen Christ by the Holy Spirit through faith.

Union with Christ is not merely a metaphor. Paul's "in Christ" language (used over 160 times in his letters) describes a genuine spiritual reality: believers are joined to Christ so intimately that His death counts as their death, His resurrection as their resurrection, His righteousness as their righteousness, and His life as their life. "It is no longer I who live, but Christ who lives in me" (Galatians 2:20).

The ecclesiological implication is direct: if every believer is united to Christ, then every believer is united to every other believer in Christ. The church is not an association of like-minded individuals who chose to affiliate; it is an organic reality created by the Spirit's work of uniting sinners to the Savior. You cannot be "in Christ" and not be "in" His body. Union with Christ and incorporation into the church are inseparable realities.

This is why the Reformed tradition has always insisted that conversion and church membership belong together. To receive Christ is to be incorporated into His body. To be born again is to be born into a family. The Spirit who regenerates is the same Spirit who baptizes into one body. There is no such thing, in the New Testament, as a saved person who is not part of the church.

Conclusion: The Church That Was Always Meant to Be

The church is not an accident of history. It is not a human invention that happened to emerge in first-century Palestine. It is not God's backup plan after Israel failed. The church is the eternal purpose of the triune God—chosen before the foundation of the world, revealed as a mystery in the fullness of time, destined to display God's glory to the cosmos for all eternity.

When you grasp this, everything about your relationship to the church changes. You no longer see it as optional, as one religious activity among many. You see it as the community for which the universe was made. You see your place in it not as a consumer choosing a product but as a member grafted by grace into the body of Christ, elected before time, sealed by the Spirit, and destined for glory.

The church is heading somewhere. It has a future so glorious that Paul can only stammer about "the riches of his glorious inheritance in the saints" (Ephesians 1:18). And every believer, from the most visible leader to the most obscure member, is part of this eternal plan—not as a spectator, but as a participant in the most important thing God is doing in the world.