This generation is not always one of time of typical 40 years, but of generation, of type of mankind.
As in unbelief, the evil age of unbelieving mankind.
All unbelief will pass away with the second coming of Christ
G1074 - γενεά geneá, ghen-eh-ah'; from (a presumed derivative of) ; a generation; by implication, an age (the period or the persons):—age, generation, nation, time.
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STRONGS G1074:
γενεά, -ᾶς, ἡ, (ΓΕΝΩ, γίνομαι [cf. Curtius, p. 610]); Sept. often for דּוֹר; in Greek writings from Homer down;
1. a begetting, birth, nativity: Herodotus 3, 33; Xenophon, Cyril 1, 2, 8, etc.; [others make the collective sense the primary significance, see Curtius as above].
2. passively, that which has been begotten,
men of the same stock, a family;
a. properly, as early as Homer; equivalent to מִשְׁפָּחַה,
Genesis 31:3, etc. σῴζειν Ῥαχάβην κ. τὴν γενεὰν αὐτῆς, Josephus, Antiquities 5, 1, 5. the several ranks in a natural descent, the successive members of a genealogy:
Matthew 1:17, (ἑβδόμη γενεὰ οὗτός ἐστιν ἀπὸ τοῦ πρώτου, Philo, vit. Moys. i. § 2).
b. metaphorically, a race of men very like each other in endowments, pursuits, character; and especially in a bad sense a perverse race: Matthew 17:17;
Mark 9:19;
Luke 9:41;
Luke 16:8; [
Acts 2:40].
3. the whole multitude of men living at the same time:
Matthew 24:34;
Mark 13:30;
Luke 1:48 (πᾶσαι αἱ γενεαί);
Luke 21:32;
Philippians 2:15; used especially of the Jewish race living at one and the same period:
Matthew 11:16;
Matthew 12:39,
41f,
45;
Matthew 16:4;
Matthew 23:36;
Mark 8:12,
38;
Luke 11:29f,
32,
50;
Luke 17:25;
Acts 13:36;
Hebrews 3:10; ἄνθρωποι τῆς γενεᾶς ταύτης,
Luke 7:31; ἄνδρες τῆς γεν. ταύ.,
Luke 11:31; τὴν δὲ γενεὰν αὐτοῦ τίς διηγήσεται, who can describe the wickedness of the present generation,
Acts 8:33 (from
Isaiah 53:8 Sept.) [but cf. Meyer, at the passage].
4. an age (i. e. the time ordinarily occupied by each successive generation), the space of from 30 to 33 years (Herodotus 2, 142, and others; Heraclitus in Plutarch, def. orac. c. 11), or ὁ χρόνος, ἐν ᾧ γεννῶντα παρέχει τὸν ἐξ αὐτοῦ γεγεννημένον ὁ γεννήσας (Plutarch, the passage cited); in the N. T. common in plural:
Ephesians 3:5 [Winers Grammar, § 31, 9 a.; Buttmann, 186 (161)]; παρῳχημέναις γενεαῖς in ages gone by,
Acts 14:16; ἀπὸ τῶν γενεῶν for ages, since the generations began,
Colossians 1:26; ἐκ γενεῶν ἀρχαίων from the generations of old, from ancient times down,
Acts 15:21; εἰς γενεὰς γενεῶν
unto generations of generations, through all ages, forever (a phrase which assumes that the longer ages are made up of shorter; see αἰών, 1 a.):
Luke 1:50 R L (דּוֹרִים לְדוֹר,
Isaiah 51:8); εἰς γενεὰς κ. γενεάς unto generations and generations, ibid. T Tr WH equivalent to וָדוֹר לְדוֹר,
Psalm 89:2;
Isaiah 34:17; very often in the Sept.; [add, εἰς πάσας τὰς γενεὰς τοῦ αἰῶνος τῶν αἰώνων,
Ephesians 3:21, cf. Ellicott at the passage] (γενεά is used of a century in
Genesis 15:16, cf. Knobel at the passage, and on the senses of the word see the full remarks of Keim, iii. 206 [v. 245 English translation]).
Examples
Matthew 11
11 “Assuredly, I say to you, among those born of women there has not risen one greater than John the Baptist; but he who is least in the kingdom of heaven is greater than he. 12 And from the days of John the Baptist until now the kingdom of heaven suffers violence, and the violent take it by force. 13 For all the prophets and the law prophesied until John. 14 And if you are willing to receive
it, he is Elijah who is to come. 15 He who has ears to hear, let him hear!
16 “
But to what shall I liken this generation? It is like children sitting in the marketplaces and calling to their companions, 17 and saying:
‘We played the flute for you,
And you did not dance;
We mourned to you,
And you did not [b]lament.’
18 For John came neither eating nor drinking, and they say, ‘He has a demon.’ 19 The Son of Man came eating and drinking, and they say, ‘Look, a glutton and a [
c]winebibber, a friend of tax collectors and sinners!’ But wisdom is justified by her [
d]children.”
Woe to the Impenitent Cities
20 Then He began to rebuke the cities in which most of His mighty works had been done, because they did not repent: 21 “Woe to you, Chorazin! Woe to you, Bethsaida! For if the mighty works which were done in you had been done in Tyre and Sidon, they would have repented long ago in sackcloth and ashes. 22 But I say to you, it will be more tolerable for Tyre and Sidon in the day of judgment than for you. 23 And you, Capernaum, who[
e] are exalted to heaven, will be brought down to Hades; for if the mighty works which were done in you had been done in Sodom, it would have remained until this day. 24 But I say to you that it shall be more tolerable for the land of Sodom in the day of judgment than for you.”