Greek word · G2178

ἐφάπαξ

ephapax

once/at once

BDAG gives two senses: (1) "at one time, all together" (1 Cor 15:6, appearing to more than 500 at once); (2) "once for all, once and never again" (Rom 6:10; Heb 7:27; 9:12; 10:10). It is a strengthened form of ἅπαξ, "once."

Appears 5 times in 5 verses of the Greek New Testament. · Updated October 25, 2026

What it means

ἐφ-άπαξ,

adv.

1. once for all (Eupol.): Romans 6:10 Hebrews 7:27 9:12 10:10.

2. at once: 1 Corinthians 15:6.†

(AS)

From G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922), via STEPBible.org (CC BY 4.0).

In depth

From the study of Romans 6:10

Range of meaning: BDAG gives two senses: (1) "at one time, all together" (1 Cor 15:6, appearing to more than 500 at once); (2) "once for all, once and never again" (Rom 6:10; Heb 7:27; 9:12; 10:10). It is a strengthened form of ἅπαξ, "once."
Against the English: The KJV's "once" and the WEB's "one time" are correct but thin. In modern English "once" can just mean "on one occasion" or even "formerly." "Once for all" (BSB, NIV, ESV, NASB) keeps both the uniqueness and the finality.
How it drifted: Older English "once" carried more weight, and the word has weakened since.
Used elsewhere in the period: Hebrews uses it for Christ's single sacrifice, set against the priests' daily, repeated offerings (7:27; 9:12; 10:10). Paul's point here is slightly different: the contrast is with dying again, not with repeated sacrifices. The Vulgate renders it semel, "once."

From the study of Hebrews 9:12

Range of meaning: 'Once for all', decisively and without repetition. It can also mean 'at one time, all together' (1 Cor 15:6, 'more than five hundred at once').
Against the English: KJV 'once' is ambiguous in modern English and can sound like 'formerly' or 'one time back then'. 'Once for all' (BSB, WEB, ESV, NASB) captures that the act is final.
How it drifted: Early modern 'once' carried the sense of 'one single time', but today it reads more naturally as 'at some point in the past'.
Used elsewhere in the period: Heb 7:27 (he offered himself 'once for all', unlike daily sacrifices); 10:10 ('the offering of the body of Jesus Christ once for all'); Rom 6:10 (he died to sin once for all). Hebrews also uses the simpler ἅπαξ for the same idea (9:7, 26, 28).

From the study of Hebrews 10:10

Range of meaning: Formed from epi + hapax ('once'). It means (1) once and for all, a single time never to be repeated; (2) at one time, all together (1 Cor 15:6, 'more than five hundred brothers at once').
Against the English: 'Once for all' is a good English idiom for 'once, decisively, never again.' Many readers hear it instead as 'once, for all people.' That is not what the word says. Its whole force is about time and finality, not about how many people are included.
How it drifted: The English idiom 'once for all' (shortened from 'once and for all') is easily split in the ear into 'once' + 'for all [people].' Meanwhile 1 Pet 3:18 ('Christ suffered once for sins, the righteous for the unrighteous') and 2 Cor 5:14–15 ('one died for all') get blended into it in sermon memory.
Used elsewhere in the period: In the NT: Rom 6:10 ('the death he died he died to sin once for all'); Heb 7:27 ('this he did once for all when he offered up himself'); 9:12 ('he entered once for all into the holy places'); 10:10. The simple form hapax carries the same contrast in Heb 9:7, 26, 28 and 10:2, where worshipers 'once cleansed' would no longer feel guilt.

Where it appears

Romans · 1

Romans 6:10 ἐφάπαξ· once for all;

The death He died, He died to sin once for all; but the life He lives, He lives to God.

Here: It happened once and will never be repeated, and it is final. It picks up "no longer dies" in verse 9: there is no second death for Christ, because the first one did everything it needed to do.

1 Corinthians · 1

1 Corinthians 15:6 ἐφάπαξ at once

After that, He appeared to more than five hundred brothers at once, most of whom are still living, though some have fallen asleep.

Hebrews · 3

Hebrews 7:27 ἐφάπαξ once for all

Unlike the other high priests, He does not need to offer daily sacrifices, first for His own sins and then for the sins of the people; He sacrificed for sin once for all when He offered up Himself.

Here: An emphatic 'once', meaning once and never needing to be repeated. It answers 'day by day' directly and is a key word in Hebrews (9:12; 10:10).
Hebrews 9:12 ἐφάπαξ once for all

He did not enter by the blood of goats and calves, but He entered the Most Holy Place once for all by His own blood, thus securing eternal redemption.

Here: Not 'once upon a time' but 'once, and never again needed'. It sets this entry against the high priest's yearly entry (9:7, 25) and the daily sacrifices (7:27).
Hebrews 10:10 ἐφάπαξ.¶ once for all.

And by that will, we have been sanctified through the sacrifice of the body of Jesus Christ once for all.

Here: The final, emphatic word: a single, unrepeatable event. It contrasts directly with the priests' sacrifices 'day after day… again and again' in v. 11.

Word data: STEPBible.org (CC BY 4.0), main text only.