3. Because the Spirit conforms believers to the image of Christ in purity and love by deepening our faith in Christ and grasp of the implications of the gospel, our preaching must fix our hearers’ minds and hearts on the transforming glory of Jesus the Christ.
How can we and our hearers have our hearts transformed into the image of Christ? Through hearing Christ preached! Paul’s aim in preaching was not just to “get people saved,” slipping through heaven’s door by the skin of their teeth. He wanted his hearers to live a life of vibrant, joyful, grateful trust in Christ by the power of the Holy Spirit. He preached evangelistic sermons to call unbelievers to faith in Jesus, and then he kept right on preaching the same gospel, because he knew that the only way anyone can be presented “perfect” to God is if he or she is “perfect in Christ” (Col. 1:28)—drawing life from Christ, as a branch depends for life on the grapevine to which it is joined.
In the 19th century Thomas Chalmers, pastor and theological professor of the Church of Scotland, preached a classic sermon called “The Expulsive Power of a New Affection.” He said that those who want to see people turn away from the world and its sinful and self-destructive appetites, and to pursue holiness of life instead, can follow one of two strategies. One is to try to convince our listeners that sinning is bad for them, that it will let them down and lead to frustration, desperation, and death. This approach, said Chalmers, never really works in the long run, because it only creates a vacuum in the heart, with nothing to fill the void.
What is needed, said Chalmers, is a new affection so strong that it expels the old from our hearts—something so attractive that sin and self-centeredness no longer seem appetizing. Now, asked Chalmers, what “new affection” is strong enough to break our own and our members’ attachment to sin? The grateful love that flows from the gracious work of Christ! The assurance of the Father’s love that is grounded in the gospel puts to rest our fears that God will reject us if we fail to “measure up,” and transforms obedience from mere duty to a delightful opportunity to express our love for the God who first loved us.
To the extent that people go away from our preaching with the impression that God’s approval is contingent on their performance, their relationship with God remains a business transaction in which, consciously or not, they see themselves as trading their best efforts at self-discipline for some reassurance that they have done enough to stay on God’s “good side.” That quid-pro-quo business arrangement, though, can never generate the delight in God and grateful love that outshines the allure of sin. Only the assurance that comes from resting in what Christ has done for us can overwhelm us with love and wonder over his grace, and this will fire our passion for holiness.
In Galatians 3:1-3 Paul insisted—in contradiction to the Judaizers—that the only way for the Gentile believers of Galatia to “be perfected” (ἐπιτελεῖσθε), to complete the spiritual pilgrimage on which they had set out by trusting the message of Christ crucified, was to stay on that same course: not departing from the dependence on Christ and his Spirit in which they began, not refocusing their reliance on “the flesh,” their efforts and record of Torah-observance. Paul goes on to show why the Judaizers’ formula for spiritual maturity cannot work: it contradicts God’s purpose for the Law of Moses, trying to force the Law to do a task that God did not design it to do: In Galatians 3:21, Paul wrote: “If a law had been given that could give life, then righteousness would indeed be by the law,” implying that the law could never impart the spiritual life that would enable us to fulfill its requirements.
The Law’s impotence, as Law, to instill the life and power of the Spirit into the human heart, is the backdrop of Paul’s victorious announcement in Romans 8:1-4:
There is therefore now no condemnation for those who are in Christ Jesus. For the law of the Spirit of life has set you free in Christ Jesus from the law of sin and death. For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit.
In the first sentence, “There is therefore now no condemnation for those who are in Christ Jesus,” Paul reaffirms the thrust of Romans 3-5, that our justification and assurance are grounded in Jesus, not in ourselves or our efforts. Then Paul develops the implications of justification for sanctification, as he discussed in Romans 6-7, contrasting the liberating power of the Spirit of life to the law’s impotence to break through the syndrome of sin and death: “For the law of the Spirit of life has set you free in Christ Jesus from the law of sin and death. For God has done what the law, weakened by the flesh, could not do.”
What, precisely, could the law not do? (Paul’s Greek is striking, Τὸ γὰρ ἀδύνατον τοῦ νόμου, “the law’s impossible thing.”) The monologue of Romans 7:7-25 had dramatized the reality that the flesh—our sin-disabled human nature, devoid of the Spirit’s life—had weakened the law, so it could not empower the obedience that it defined and demanded (Johnson, “Function of Romans, 3-59). And the law’s impotence is shown most clearly in what God in fact did through “his own Son,” as Paul says in 8:3-4: First, “by sending his own Son in the likeness of sinful flesh and for sin, [God] condemned sin in the flesh.” Christ’s death as our representative answered sin’s indictment of the guilty (Rom. 3:21-26; 4:24-25) and broke sin’s slavery over its captives (6:1-14). Second, the result produced by the Spirit in believers is expressed in verse 4: “in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit.” By the Spirit’s powerful presence believers now “walk”—now conduct their lives—controlled by new values, affections, and desires. Paul had said earlier that believers “have been set free from sin and have become slaves of God” (6:22). The cross and the Spirit of Christ, embraced by growing faith and deepening understanding, converge to change motives and desires, and therefore to change words and deeds, in a way that preaching the Law as duty could never achieve.
The result of our freedom from the law as the condition of our acceptance by God is that we begin to find “the law’s righteous requirement fulfilled in us”—not only “on our behalf” (though it is true that Christ kept its every command flawlessly for us), but also in our desires and behavior: Later in Romans (13:8-10) Paul returns to the theme that those who “walk by the Spirit” will see the law fulfilled in their affections and actions:
Owe no one anything, except to love each other, for the one who loves another has fulfilled the law. For the commandments, "You shall not commit adultery, You shall not murder, You shall not steal, You shall not covet," and any other commandment, are summed up in this word: "You shall love your neighbor as yourself." Love does no wrong to a neighbor; therefore love is the fulfilling of the law.
The law—whether explicit commandment or moral example—sets the standard for God-pleasing thoughts, words, and actions; but it cannot, in itself, instill the life, love, and hope that move us toward conformity to the image of Christ. If we want our preaching to serve that purpose, the only power that can effect such a new creation is for our hearers to “behold the glory of the Lord” (2 Cor. 3:18), as we preach Jesus Christ crucified, risen, reigning, and returning.
Not only does Christ-centered preaching fit God’s purpose for the Bible and the apostles’ example, but it is also the means that God uses to effect radical heart transformation. So preaching Christ from all the Scriptures fulfills the purposes of preaching, as the Larger Catechism lists them, “…enlightening, convincing, and humbling sinners; … driving them out of themselves, and drawing them unto Christ; … conforming them to his image, and subduing them to his will; … strengthening them against temptations and corruptions; … building them up in grace, and establishing their hearts in holiness and comfort through faith unto salvation” (A. 155).
Now that apostolic homiletics has been defined and defended, next Wednesday's post moves to substructure and strategies.