In Galatians, Paul describes how he received his gospel as “an apocalypse of Jesus Christ” (Gal. 1:12). That claim is related to a decisive moment in Paul's biography: the road to Damascus. If we want to understand Paul's gospel I think it helps to linger over this experience, pondering Paul's “before” and “after.”
Imaginatively, I've suggested that it helps to picture Paul's mental state and worldview the morning he set out to arrest members of a heretical messianic sect. Paul's world, at that moment, was clear and coherent. The law was holy, righteous, and good (Rom. 7:12). The problem was not the law, but the need for obedience. And what secured obedience was zeal. In this, Paul stood in the footsteps of Phinehas.
In the Old Testament story of Phinehas, (murderous) zeal for God’s honor was explicitly “credited as righteousness” (Num. 25:11–13; Ps. 106:30–31). Phinehas acts decisively in the face of covenantal compromise, and his zeal turns away God’s wrath. The story created a script. If the law is good, then what is required is passionate adherence to it. Zeal would make you righteous.
And that is exactly what Paul was doing on the road to Damascus. As he later described it, “as for zeal, persecuting the church; as for righteousness based on the law, faultless” (Phil. 3:6). Regarding later, especially Protestant, visions of the gospel, Paul was not struggling with guilt on the road to Damascus. Nor was Paul trying to “earn his salvation” in some anxious, introspective way. Paul was doing exactly what he believed God required. As I've shared before, the equation in Paul's head that morning was simple:
The Law + Zeal = Righteousness
And then came the apocalypse.
On the road, Paul encounters the risen Jesus: “Saul, Saul, why are you persecuting me?” And in that confrontation everything falls apart. The zeal Paul believed would be credited as righteousness is exposed as participation in Israel's catastrophe.
For three days Paul sits in blindness. And it's is here, in this darkness, where his gospel begins to take shape. What is revealed to Paul isn't just that Jesus is the Messiah, but that Israel, in her zeal for the law, had crucified her Messiah. And Paul, with that same zeal, was continuing this failure.
In short, the very thing that was supposed to produce righteousness had produced the worst possible outcome. Instead of righteousness, zeal had produced covenantal failure.
This realization, I think, is the clearest path into Paul’s gospel. Because I think it raises the crucial question Paul pondered for three days as he sat in darkness: What went wrong?
Paul’s answer unfolds most fully in Romans 5–8. The first thing Paul insists upon, a point often missed, is that the problem wasn't the law. Again, Paul is clear on this issue: the law is holy, righteous, and good (Rom. 7:12). This part of Paul's worldview–his high view of the law–remained intact after this encounter with Jesus on the road to Damascus. The problem, as Paul came to see it, is what happens when the law encounters human flesh (sarx).
Sarx simply means “flesh,” as in meat. But for Paul, sarx is existentially freighted and names how human existence has been weakened by the powers of Sin and Death. As Paul says, “For the mind set on the flesh is hostile to God; it does not submit to God’s law, indeed it cannot” (Rom. 8:7). This incapacity to submit to God's law–"indeed it cannot"–is the deep cause of Israel's catastrophe.
Stepping back, the issue here is not legalism or “works-based righteousness.” That is the common misconception, especially in Protestant circles. Our desire to obey God is right and good. For Paul, the problem is, rather, our moral incapacity. Sarx lacks the ability to carry out what the law demands and what we, ourselves, desire: “For I do not do what I want, but I do the very thing I hate” (Rom. 7:15). And when the law meets this incapacity, Sin seizes the opportunity: “For sin, seizing the opportunity afforded by the commandment, deceived me, and through the commandment put me to death” (Rom. 7:11).
This is why the Phinehas formula failed. Zeal cannot overcome Sin. Worse, zeal, operating within sarx, becomes entangled in the very powers it is trying to resist. What Paul thought would be “credited as righteousness” became the means by which he opposed the Messiah.
This is what was revealed to Paul on the road to Damascus. Not simply that he was mistaken, but that the entire project of attaining righteousness through zeal had gone catastrophically wrong. More, if zeal had been enough, there would have been no need for Christ to die. As Paul says, “If righteousness comes through the law, then Christ died for nothing” (Gal. 2:21). Israel had zeal in abundance. Paul himself had zeal. But zeal proved powerless before the dominion of Sin and Death.
The Law + Sarx = Covenantal Failure
Which means our predicament runs deeper than effort. And if that is so, the solution must go deeper as well.
Which brings us to the heart of Paul’s gospel, its pneumatological core. What Christ accomplishes in his death and resurrection is not simply forgiveness. Christ defeats the powers that have weakened sarx. Christ breaks the dominion of Sin and Death and inaugurates a new reality. This new reality is given through the Spirit: “If the Spirit of him who raised Jesus from the dead dwells in you, he who raised Christ Jesus from the dead will also give life to your mortal bodies” (Rom. 8:11).
Through the Spirit, the power of Death is overcome. Through the Spirit, the weakness of sarx is addressed. Through the Spirit, the situation that made obedience impossible is fundamentally altered. What the law could not do, weakened as it was by the flesh, God did: “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” (Rom. 8:3–4).
The point is straightforward. The Spirit gives us the capacity to follow God’s commands. The Spirit does what zeal could not do. As Paul says, “the law of the Spirit of life in Christ Jesus has set you free from the law of sin and death” (Rom. 8:2). Further, “if by the Spirit you put to death the deeds of the body, you will live” (Rom. 8:13). Through the Spirit, we are no longer captive to the power that made obedience impossible. Through the Spirit, we bear the fruit of God’s kingdom: “But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, self-control” (Gal. 5:22–23). This is what obedience looks like when it is pneumatologically empowered.
The Law + the Spirit = Fruitful Life
Pneumatology, therefore, is the very heart of Paul’s gospel. Pneumatology is the hinge. Without the Spirit, the catastrophe revealed on the road to Damascus remains unaddressed. The Spirit infuses life, empowers obedience, and sustains faith in ways that human effort, zeal, and law-keeping cannot. To understand Paul is to see that the Spirit is the gospel.
As Paul puts it, the gospel is the power of God for salvation (Rom. 1:16).
