“propitiation”

The word in two contexts

Hilastērion (ἱλαστήριον) appears in two principal New Testament passages:

• Hebrews 9:5 — the cover of the ark of the covenant, the kapporeth in Hebrew, where the high priest sprinkled blood on the Day of Atonement. Almost universally translated “mercy seat” or “atonement cover” in English.
• Romans 3:25 — Christ “whom God put forward as a hilastērion by His blood, through faith” (BSB: “as the atoning sacrifice”). Translations split along three lines. The KJV preserves “propitiation” (its traditional rendering), and the ESV follows it. The RSV broke with that tradition by rendering the word “expiation,” dropping the deflect-wrath sense in favour of a covering-of-sin sense. Modern copyrighted translations (NIV, NRSV, NLT, NASB, CSB) tend to cluster around atonement-sacrifice phrasings closer to the BSB.

The same Greek word, translated as a piece of temple furniture in Hebrews and as a sacrificial event in Romans.

The Septuagint background

In the Septuagint (Greek translation of the Hebrew Bible, 3rd–2nd century BC), hilastērion is the standard translation of the Hebrew kapporeth (כַּפֹּרֶת) — the lid of the ark of the covenant. Exodus 25:17-22, Leviticus 16:14-15, and elsewhere use hilastērion in this sense.

The kapporeth / hilastērion was the place where, on Yom Kippur, the high priest sprinkled blood as part of the atonement ritual. It was the place where atonement occurred, not the act of atonement itself.

The Romans 3:25 question

What does Paul mean when he says God put Christ forward as a hilastērion?

• Reading 1 — propitiation as wrath-satisfaction. Christ’s death satisfies divine wrath against sin. The KJV’s “propitiation” carries this connotation. Defended by traditional Reformed and evangelical theology.
• Reading 2 — expiation as sin-removal. Christ’s death removes the contamination of sin without specifying divine wrath. The RSV’s “expiation” carries this. Defended notably by C.H. Dodd in the mid-twentieth century.
• Reading 3 — Christ as the new mercy seat / place of atonement. Christ is the new kapporeth — the location where God meets sinners and atonement is made. Defended in some recent scholarship (notably N.T. Wright) drawing on the LXX background.

All three readings are within the lexical range of hilastērion. The third reading has the strongest direct lexical support from the Septuagint usage; the first reading has the strongest theological-traditional support.

What this means

The translation choice is not neutral. Different English Bibles render the word differently because translators are making choices about the underlying theology. A reader looking at “propitiation” in Romans 3:25 (KJV/ESV) and “atonement cover” in Hebrews 9:5 may not realise the same Greek word lies behind both.

For the broader biblical concept of atonement and the Tyndale-era English vocabulary, see our atonement entry.