ἄρα, an illative particle (akin, as it seems, to the verbal root ΑΡΩ to join, to be fitted [cf. Curtius, § 488; Vanicek, p. 47]), whose use among native Greeks is illustrated fully by Kühner, ii., §§ 509, 545; [Jelf, §§ 787-789], and Klotz ad Devar. ii., pp. 160-180, among others; [for a statement of diverse views see Bäumlein, Griech. Partikeln, p. 19f]. It intimates that, "under these circumstances something either is so or becomes so" (Klotz, the passage cited, p. 167): Latin igitur, consequently, [differing from οὖν in 'denoting a subjective impression rather than a positive conclusion.' Liddell and Scott (see 5 below)]. In the N. T. it is used frequently by Paul, but in the writings of John and in the so-called Catholic Epistles it does not occur. On its use in the N. T. cf. Winer's Grammar, §§ 53, 8 a. and 61, 6. It is found:
1. subjoined to another word: Romans 7:21; Romans 8:1; Galatians 3:7; ἐπεὶ ἄρα since, if it were otherwise, 1 Corinthians 7:14; [1 Corinthians 5:10, cf. Buttmann, § 149, 5]. When placed after pronouns and interrogative particles, it refers to a preceding assertion or fact, or even to something existing only in the mind: τίς ἄρα who then? Matthew 18:1 (i. e. one certainly will be the greater, who then?); Matthew 19:25 (i. e. certainly some will be saved; you say that the rich will not; who then?); Matthew 19:27; Matthew 24:45 (I bid you be ready; who then etc.? the question follows from this command of mine); Mark 4:41; Luke 1:66 (from all these things doubtless something follows; what, then?); Luke 8:25; Luke 12:42; Luke 22:23 (it will be one of us, which then?); Acts 12:18 (Peter has disappeared; what, then, has become of him?). εἰ ἄρα, Mark 11:13 (whether, since the tree had leaves, he might also find some fruit on it); Acts 7:1 [Rec.] (ἄρα equivalent to 'since the witnesses testify thus'); Acts 8:22 (if, since thy sin is so grievous, perhaps the thought etc.); εἴπερ ἄρα, 1 Corinthians 15:15, (אִם־נָא, εἰ ἄρα, Genesis 18:3). οὐκ ἄρα, Acts 21:38 (thou hast a knowledge of Greek; art thou not then the Egyptian, as I suspected?); μήτι ἄρα (Latin num igitur), did I then etc., 2 Corinthians 1:17.
2. By a use doubtful in Greek writings (cf. Buttmann, 371 (318); [Winers Grammar, 558 (519)]) it is placed at the beginning of a sentence; and so, so then, accordingly, equivalent to ὥστε with a finite verb: ἄρα μαρτυρεῖτε [μάρτυρές ἐστε T Tr WH], Luke 11:48 (Matthew 23:31 ὥστε μαρτυρεῖτε); Romans 10:17; 1 Corinthians 15:18; 2 Corinthians 5:14 (2 Corinthians 5:15) (in L T Tr WH no conditional protasis preceding); 2 Corinthians 7:12; Galatians 4:31 (L T Tr WH διό); Hebrews 4:9.
3. in an apodosis, after a protasis with εἰ, in order to bring out what follows as a matter of course (German so ist ja the obvious inference is): Luke 11:20; Matthew 12:28; 2 Corinthians 5:14 (2 Corinthians 5:15) (R G, a protasis with εἰ preceding); Galatians 2:21; Galatians 3:29; Galatians 5:11; Hebrews 12:8; joined to another word, 1 Corinthians 15:14.
4. with γέ, rendering it more pointed, ἄραγε [L Tr uniformly ἄρα γε; so R WH in Acts 17:27; cf. Winers Grammar, p. 45; Lipsius Gram. Untersuch., p. 123], surely then, so then (Latin itaque ergo): Matthew 7:20; Matthew 17:26; Acts 11:18 (L T Tr WH omit γέ); and subjoined to a word, Acts 17:27 [Winer's Grammar, 299 (281)].
5. ἄρα οὖν, a combination peculiar to Paul, at the beginning of a sentence (Winers Grammar, 445 (414); Buttmann, 371 (318) ["ἄρα ad internam potius caussam spectat, οὖν magis ad externam." Klotz ad Devar. ii., p. 717; ἄρα is the more logical, οὖν the more formal connective; "ἄρα is illative, οὖν continuative," Winers, the passage cited; cf. also Kühner, § 545, 3]) [R. V.] so then (Latin hinc igitur): Romans 5:18; Romans 7:3, 25; Romans 8:12; Romans 9:16, 18; Romans 14:12 (L Tr omit WH brackets οὖν); Romans 14:19 [L marginal reading ἆρα]; Galatians 6:10; Ephesians 2:19; 1 Thessalonians 5:6; 2 Thessalonians 2:15.

Related entry:

[ἄραγε, see ἄρα 4.]