We are dealing with the
hilask- word family, a collection of terms that occupy a single semantic field:
- hilasmos (ἱλασμός) a noun denoting an atoning sacrifice or means of atonement,
- hilaskomai (ἱλάσκομαι), a verb meaning to make atonement or to appease, and
- hilastērion (ἱλαστήριον), a noun referring to the place or means of atonement (e.g., Heb 9:5).
What often causes confusion is that English theological debate has fixated on
hilastērion in Romans 3:25, then retrojected that debate onto
hilasmos. And yet the semantic field is the same: these terms concern atonement conceived as a Godward action that deals with sin
and its consequences, not just moral cleansing in abstraction (expiation alone). Paul is explaining how God remains just while justifying the ungodly. The problem, crucially, is divine forbearance: God had “passed over former sins,” a restraint that creates a judicial tension. If sins go unpunished, then God’s justice is called into question.
Propitiation is Paul’s answer to that problem. He argues that Christ himself is that
hilastērion—not simply the agent of propitiation but the very locus where wrath is dealt with—deliberately evoking the mercy seat that was sprinkled with atoning blood on the Day of Atonement. The background is unambiguously Levitical and cultic, where we see that blood was offered to avert divine wrath by satisfying God’s justice. It pointed forward to the cross of Christ which functions covenantally as life-for-life satisfaction under divine justice. Christ is the true Lamb whose blood turns aside divine wrath from those for whom it was shed.
Cognate terms appear in Hebrews 2:17, 1 John 2:2 and 4:10, where Christ’s atoning work is explicitly described as propitiatory. In each case, God is the object, sin under judgment is the problem, and deliverance from wrath is the result. The cross is thus forensic and public, God’s clearest and most personal demonstration that sin is judged and mercy is dispensed without injustice.
This is why expiation-only readings fail. Cleansing language alone cannot account for verse 26: “so that he might be just and the justifier of the one who has faith in Jesus.” If the cross only removes sin as defilement, the question of justice remains unanswered. Sin would be removed but not judged. In such a picture, how could God be the justifier, much less just? The judicial tension Paul identified would persist.
John Owen identified four necessary elements of any true propitiation: (1) an offence to be taken away, (2) a person offended who needs to be pacified, (3) a guilty offending person, and (4) a sacrificial means by which the offence is answered. His framework aligns precisely with Paul’s argument. God is the offended party; sin is a real offence; sinners are truly guilty; and satisfaction must be rendered. The cross is not God arbitrarily changing his posture toward sin but judging it in the Substitute in a manner consistent with his own righteous and loving nature.
Detach Romans 3:25-26 from propitiation and Paul’s argument falls apart. Without wrath answered, righteousness demonstrated, and justice upheld, justification becomes a legal fiction. Paul will not allow that. Neither should we.