Once (at; for all) - Vine's Expository Dictionary of New Testament Words

Once (at; for all)

[ 1,,G530, hapax ]
(a) once, one time," 2 Corinthians 11:25; Hebrews 9:7, Hebrews 9:26-Hebrews 9:27; Hebrews 12:26-Hebrews 12:27; in the phrase "once and again," lit., "once and twice," Philippians 4:16; 1 Thessalonians 2:18;
(b) "once for all," of what is of perpetual validity, not requiring repetition, Hebrews 6:4; Hebrews 9:28; Hebrews 10:2; 1 Peter 3:18; Jude 1:3, RV, "once for all" (AV, "once"); Jude 1:5 (ditto); in some mss. 1 Peter 3:20 (so the AV).

[ 2,,G2178, ephapax ]
a strengthened form of No. 1 (epi, "upon"), signifies
(a) "once for all," Romans 6:10; Hebrews 7:27, RV (AV, "once"); Hebrews 9:12 (ditto); Hebrews 10:10;
(b) "at once," 1 Corinthians 15:6.

[ 3,,G4218, pote ]
denotes "once upon a time, formerly, sometime," e.g., Romans 7:9; Galatians 1:23, 1st part, RV, "once" (AV, "in times past"); 2nd part, AV and RV, "once;" Galatians 2:6, RV marg., "what they once were" (to be preferred to the text, "whatsoever they were"), the reference probably being to the association of the twelve Apostles with the Lord during His ministry on earth; upon this their partisans based their claim for the exclusive authority of these Apostles, which Paul vigorously repudiated; in Ephesians 5:8, RV, "once" (AV, "sometimes"). See AFORETIME, LAST, LENGTH (at), TIME (past).

Note: In Luke 23:18, AV, pamplethei, denoting "with the whole multitude" (pas, "all," plethos, "a multitude"), is rendered "all at once," RV, "all together").

Vine's Expository Dictionary of New Testament Words