What are you driven by? It was a Saturday and I flipped on the TV for an extraordinarily long time. The whole day was exercise equipment, how to become real-estate rich with no money down, and Suze Orman gave me her steps to financial security. As much as we all make sport of this sort of thing, it attracts us. That’s because we are “wired” for law: tell me what to do and I’ll get it done. That is not just the American spirit, but it is human nature. God’s law is inborn, in our conscience, part of our moral makeup.

The law can direct us, but it cannot drive us, except to either despair or self-righteousness. Christians are not purpose-driven but promise-driven. Purposes are all about law. The fact that purposes are about law does not make them wrong. We need purposes! All of this is fine as long as we realize that they are law, not gospel: commands and promises are both necessary, but they do different things. Church shouldn’t be a place where the old self is revived for another week, but where it is killed and buried and the new self is created in the likeness of Christ.

The church father Augustine defined sin as being “curved in” on ourselves. While imperatives (including purposes) tend by themselves to make us more “curved in” on ourselves (either self-confidence or self-despair), only God’s promise can drive us out of ourselves and our own programs for acceptance before ourselves, other people, and God. While the Christian life according to scripture is purpose-directed, it is promise-driven. Both of our passages-Genesis 15 and Romans 4-bring this point home powerfully.

Wrestling with the Promise (Genesis 15)

Even after his military victory and the remarkable event of being offered bread and wine with a blessing from Melchizedek, Abram’s greatest problem is that he has no heir, no one to carry on the calling that God has given him. His world, as he sees it anyway, is bleak. “After these things, the word of the Lord came to Abram in a vision, ‘Do not be afraid, Abram, I am your shield; your reward shall be very great'” (Gen. 15:1). Abram and Sarai had been called out of the barrenness of moon-worship in the city of Ur by God’s powerful Word, which created faith in the promise (12:1). Notice in this opening address, it is sheer promise. God simply declares, “I am your shield. Your reward shall be great.”

Yet Abram wonders, “O Lord God, what will you give me, for I continue childless, and the heir of my house is Eliezar of Damascus? … You have given me no son, and so a slave born in my house is to be my heir” (vv. 2-3). The empirical facts of the case-what Abram sees, appear to be overwhelming evidence against the testimony of the promise. Nevertheless, God counters again with the promise, offering the innumerable stars as a sign of the teeming offspring who will come from his loins. “And [Abram] believed the Lord; and the Lord reckoned it to him as righteousness” (vv. 5-6). Abram’s response is not one of blind optimism or positive thinking. Abram finds himself believing.

Faith does not create; it receives. It does not make the invisible visible or the future present or hope reality. It receives that which is already given. Grace precedes faith. Further, there is no way around the forensic or legal character of this Hebrew verb, “declared.” It is chashav, referring to a courtroom judgment, not a process. There Abram stood, wicked and helpless, and yet at the same time-by virtue solely of the promise declared to him, received by faith, was declared righteous.

The preaching of the promise created justifying faith and this sign and seal now confirms and ratifies it. Out of his confession of faith, Abram now continues his pilgrimage not on the basis of his physical vigor or Sarai’s fertility, but on the sole basis of the Word. Sarai’s infertile womb is the canvas upon which God will paint a new creation. And they both get renamed. The promise gives them a new identity.

The Fulfillment of the Promise (Romans 4:13-25)

Paul brings Abraham to the witness stand as an example to us, not chiefly as someone whose holiness we can emulate (have you read the story?), but primarily as someone for whom the promise worked even though he didn’t.

Paul is contrasting law-logic with promise-logic. The law is not the problem, but we are, and the law simply points that out. We know the law by nature; nobody has to teach at least its rudimentary principles to us (Rom. 1 and 2). When we turn to our common sense, reason, experience, or what we see in order to determine our relationship to God, it is always the law that has the last word. Law-logic is entirely appropriate for those created in God’s image, designed and equipped to reflect God’s righteousness in every way, but it says nothing about how law-breakers can be saved from its judgment.

In Romans 3:21-26, Paul announces that law-logic can only announce the righteousness that God is and which therefore condemns us who have failed to conform to it. Then we arrive at chapter 4. The question that throws law and promise into a sharp contrast is this: How does one obtain the inheritance of the heavenly rest? “But to him who does not work but believes on Him who justifies the ungodly, his faith is accounted for righteousness, just as David also describes the blessedness of the man to whom God imputes righteousness apart from works” (vv. 5-6).

If we read Romans 4 in the light of Paul’s argument in Romans 10, the contrast is even clearer: law-logic ascends to bring Christ down or up from the grave, while gospel-logic receives Christ as he descends to us in the preaching of the gospel. Because the law is innate (in creation) and the gospel is a surprising announcement (after the fall), climbing, ascending, attaining, doing whatever “ten steps” or following whatever “fifteen principles” is natural to us. It is not natural for us, like Abraham, to simply receive a promise, the hearing of which creates faith (Rom. 10:17). But God is never closer to us, says Paul, than when Christ is being preached to us (v. 8). God doesn’t just give us more good advice and exhortation, but the most amazing news in the world: “But to one who without works trusts him who justifies the ungodly, such faith is reckoned as righteousness” (v. 5).

It is important to recognize that God’s promises are not simply a pledge of a future reality, but bring about that reality in the present. We see this clearly in the way Paul talks about the law doing certain things and the promise doing certain things. In verse 14 of our passage he says, “For if those who are of the law are heirs, faith is made void and the promise made of no effect, because the law brings about wrath; for where there is no law there is no transgression.” The promise (or gospel) preached creates faith, just as the law actually brought about our condemnation. The law not only warns us of God’s coming wrath, it “brings about wrath,” just as the judge’s act of sentencing a criminal actually effects the criminal’s condemnation. Throughout Scripture we are taught that God’s Word is effectual: it brings about whatever God speaks, whether in creation, providence, or redemption. God’s speech is “active and living,” Scripture says.

This is why Paul returns again to the example of Abraham and Sarah as the construction site of a new creation, produced by the promise. Here is the logic: “For this reason it depends on faith, in order that the promise may rest on grace and be guaranteed to all of his descendants,” both Jew and Gentile (v 16). He adds, “As it is written, ‘I have made you the father of many nations’-in the presence of the God in whom he believed, who gives life to the dead and calls into existence the things that do not exist” (v. 17).

Just as God spoke the world into existence without any contribution from the creation itself, God speaks a new world of salvation into being. And just as Abraham is declared righteous by this proclamation then and there, Paul observes, he was declared then and there “father of many nations” despite all appearances to the contrary. “Hoping against hope, he believed that he would become ‘the father of many nations,’ according to what was said, ‘So numerous shall your descendants be'” (v. 18). God’s saying makes it so. Salvation comes, then, not by doing certain things but by hearing certain things and embracing them by faith, which is itself created by the Spirit through the preaching of the promise. Not all parts of the Word give life, as Paul says later in chapter 7 (v. 10): “And the commandment, which was to bring life, I found to bring death.” If Paul were not a transgressor, the law would pronounce him just, but as it is, it can only bring death. The promise, by contrast, brings life-out of nothing.

Conclusion: What Really Drives You?

In the concluding verses of this remarkable chapter (vv. 23-25, and the first verse of chapter 5), Paul writes,

Now the words, “it was reckoned to him,” were written not only for his sake alone, but for ours also. It will be reckoned to us who believe in him who raised Jesus our Lord from the dead, who was handed over to death for our trespasses and was raised for our justification. Therefore, since we are justified by faith, we have peace with God through our Lord Jesus Christ, through whom we have obtained access to this grace in which we stand; and we boast in our hope of sharing the glory of God.

Faith is defiance. Abraham’s faith defied every possibility that he saw, in favor of the “impossible” word that he heard. This is why “faith comes by hearing … that is, the word of faith which we preach” (Rom. 10:17). To trust in God is to distrust every other promise-maker. The world makes a lot of promises: “Try this product and you’ll be ….” Constantly buying into new fads or makeovers as so many fig leaves to hide the seriousness of our condition, we hand ourselves over to marketers who persuade us that we can attain salvation, however, we define that. Even the church can become a place where people get the idea that they exist merely to usher in the kingdom by serving on committees and being involved in a thousand programs. We have a lot of purposes, a lot of goals-some of them noble. Eventually, we will become burned out on good advice. What we need is good news.

Adapted from Michael Horton, "The Promise-Driven Life" Modern Reformation, Nov/Dec 2005. Used by permission.

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