Chapter 4 is Paul's scriptural proof of justification by faith. Having declared in 3:31 that the gospel establishes rather than abolishes the Law, Paul now demonstrates the claim by reading Genesis. The single verse he focuses on is Genesis 15:6: "Abraham believed God, and it was reckoned to him as righteousness." The Greek verb λογίζομαι (logizomai, "to reckon, count, credit") appears eleven times in this chapter — Paul drives it like a nail. He shows that (1) Abraham was justified by faith, not works (vv.1–8); (2) before he was circumcised (vv.9–12); (3) before the Law was given (vv.13–17); and (4) his faith is the pattern for all believers, Jew and Gentile (vv.18–25).
Paul's exegetical method here is rabbinic. In v.3 he quotes Genesis 15:6, then in vv.6–8 he invokes a second text — Psalm 32:1–2 — that uses the same verb (logizomai) in a related sense. This is the rabbinic principle known as gezerah shavah: "equal category" — two passages sharing a common word may be used to interpret each other. The shared word here is logizomai. Genesis 15: God reckons righteousness to Abraham. Psalm 32: God does not reckon sin against the believer. Same divine action seen from two angles: positive imputation of righteousness, negative non-imputation of sin.
Verses 4–5 are Paul's interpretive bridge — a piece of theological logic that turns the Genesis verse into a universal principle. If wages are owed, then a gift is by definition unowed. Faith corresponds to grace; works correspond to wages. The two systems cannot be combined.
The most scandalous phrase in the gospel: God justifies the ungodly. The OT calls this an abomination — and the cross is precisely how God does it justly. Christ has borne the sin; the ungodly are reckoned righteous through faith. Without the cross, the abomination remains. With the cross, it becomes the gospel.
Genesis 15:6 is the linchpin text: "Abraham believed (Hebrew: he'emin) Yahweh, and he reckoned (Hebrew: vayyachsheveha) it to him as righteousness." The Hebrew he'emin ("he believed") is the hiphil of 'aman, from which comes our word amen. Faith here is not just intellectual assent but a settled trust — saying "amen" to God's word. Psalm 32:1–2 is David's psalm of confession after his sin with Bathsheba; he celebrates the blessedness of not having sin reckoned against him, the negative side of what Genesis 15:6 affirms positively.
Paul's chronological argument is devastating in its simplicity. The narrative timeline in Genesis is unambiguous:
Genesis 15:6 — Abraham (still named Abram) believes God's promise; righteousness is reckoned to him. He is uncircumcised.
Genesis 16 — Hagar bears Ishmael (Abraham is 86).
Genesis 17 — God institutes circumcision; Abraham is now 99 years old.
Rabbinic tradition counted at least 14 years between Abraham's justification and his circumcision. Paul exploits this gap. If righteousness was reckoned to Abraham while uncircumcised, then righteousness does not require circumcision. And if it does not require circumcision for Abraham — the very founder of the circumcision covenant — it cannot require it for anyone else either.
The result: Abraham becomes the father of two groups simultaneously. He is the father of believing Gentiles (v.11, "the father of all who believe without being circumcised") AND the father of believing Jews (v.12, "the father of circumcision to those who not only are of the circumcision, but who also walk in the steps of the faith"). Note the careful qualification: Abraham is the father of those circumcised Jews who also have his faith. Mere physical descent doesn't make one a true child of Abraham.
Paul has won a genuinely radical conclusion using nothing but the timeline of Genesis. The father of the Jewish covenant was a Gentile when he was justified. To insist that Gentiles must become Jews to be saved is to make Abraham himself ineligible for the very righteousness he received.
Paul's argument in vv.13–17 is the same shape as vv.9–12 but with a different target. There: Abraham was justified before circumcision. Here: the promise was given before the Law. The Mosaic Law came 430 years after the promise to Abraham (cf. Gal 3:17). If the inheritance came through Law, it would require something that didn't exist for four centuries after the promise was made.
Verse 15 contains a critical aside: "the Law brings about wrath." Why? Because the Law makes sin into parabasis (definite transgression). Where there is no Law, sin still exists, but it is not transgression of a specific known commandment. The Law's role is not to save but to specify. This thread will become a chapter-long argument in Romans 7.
The God of Abrahamic faith is the God who gives life to the dead and calls non-being into being. He is the resurrection God, the creation God, the gospel God. The same divine character runs through Genesis 1, Genesis 15, and Easter morning — three moments where God's word produces reality where nothing was before.
Paul quotes Genesis 17:5: "I have made you a father of many nations" (av hamon goyim). The Hebrew goyim means "nations" or "Gentiles" — the same word. God explicitly told Abraham his fatherhood would extend to many nations, not just one. Paul is not stretching the text; he's pointing out what Genesis 17 already says.
Verses 23–24 are Paul's hermeneutical move. He doesn't just say Abraham was justified by faith and so are we. He says "this was not written for his sake only, but for our sake also." Paul is making a claim about how the OT functions: the texts of Genesis are not merely about Abraham; they are about all who will share Abraham's pattern of faith. The same hermeneutic appears in 1 Cor 10:11 ("written for our instruction") and 1 Cor 9:9–10.
The structural parallel between Abraham's faith and Christian faith is exact: both believe in a God who gives life to the dead. Abraham believed the God who could make a dead body father a son. Christians believe the God who raised Jesus from the dead. The God is the same; the act is the same; the faith is the same. This is why Abraham is the father of all who believe — not as ethnic ancestor but as the prototype of the faith-posture that all Christians share.
Verse 25 deserves slow reading. The pairing of handed over (cross) and raised (resurrection) with trespasses and justification creates a tight chiasm:
Christ — handed over — for our trespasses
Christ — raised — for our justification
The resurrection is essential to justification because without it, the handing-over would have been a defeat, not a victory. The empty tomb is the divine "Amen" to the cross — God's declaration that the sacrifice has been accepted, and that those united to Christ stand righteous.
Abraham did not believe a doctrine; he believed a God — the God who gives life to the dead. Christian faith is not first a set of propositions to assent to but a Person to trust. The doctrine is the description of the God we trust. Abraham trusted him before the gospel was preached; Christians trust him after the gospel has come. The faith is the same; the trustworthiness is the same; the God is the same.
"Reckoned" for logizomai throughout — LSB keeps the same English word in all 11 occurrences in the chapter. NIV varies between "credited," "counted," and "reckoned"; LSB's consistency lets the reader feel Paul's hammer-blow repetition of the bookkeeping metaphor.
"Yahweh" in Psalm 32:1–2 quotation (vv.7–8) — LSB renders kyrios as "Yahweh" in v.8 because the LXX is quoting Hebrew where the divine name appears. This preserves what David actually wrote: "Blessed is the man whose sin Yahweh will not take into account."
"Ungodly" for asebēs (v.5) — LSB keeps the OT moral weight rather than softening to "wicked" or "sinner." The same word group ran through 1:18 ("ungodliness and unrighteousness"); LSB preserves the link. Paul's claim that God justifies the ungodly is shocking only if the word retains its OT force.
"Hoping against hope" (v.18) — LSB preserves the elegant Greek wordplay par' elpida ep' elpidi ("beyond hope, upon hope") rather than smoothing to "against all hope" (NIV).
Chapter 5 will open with the consequences of justification — the peace, access, hope, and love of God poured out by the Spirit. Then Paul will trace sin and death back to Adam to set up the great Adam-Christ comparison: where sin abounded, grace abounded all the more. This launches the chapters on new life in the Spirit (6–8).
The architecture of the letter so far: chs 1–3 = the universal indictment. Ch 3:21–31 = the gospel announcement. Ch 4 = the gospel proved from Scripture (Abraham). Ch 5 = the gospel's first consequences (peace and the Adam-Christ contrast). Chs 6–8 = the gospel-shaped life.