@Fisherman
"This generation" on the lips of Jesus invariably refers to the faithless generation of his day.
The following is an excerpt from The Watchtower of May 1, 1999 (p. 11,12) which contains some elements of sound interpretation.
In
the years leading up to 66 C.E., Christians would have seen many of
the preliminary elements of the composite sign being fulfilled-wars,
famines, even an extensive preaching of the good news of the Kingdom.
(Acts 11:28; Colossians 1:23) When, though, would the end come? What
did Jesus mean when he said: 'This generation [Greek, ge.ne.a'] will
not pass away'? Jesus had often called the contemporaneous mass of
opposing Jews, including religious leaders, 'a wicked, adulterous
generation.' (Matthew 11:16; 12:39, 45; 16:4; 17:17; 23:36) So when,
on the Mount of Olives, he again spoke of "this generation,"
he evidently did not mean the entire race of Jews throughout history...
Rather, Jesus had in
mind the opposing Jews back then who would experience the fulfillment
of the sign he gave. Regarding the reference to "this
generation" at Luke 21:32, Professor Joel B. Green notes: "In
the Third Gospel, 'this generation' (and related phrases) has
regularly signified a category of people who are resistant to the
purpose of God. . . . [It refers] to people who stubbornly turn their
backs on the divine purpose." *