3) Does the word "genea" (Greek - generation) etymologically or philologically always mean people concurrent or living at "that time"? Can the word not also have a broader, more general sense? Those who want to say that the events given in the Olivet Discourse were completed in AD 70 endeavor to support their interpretation by saying that the word "generation", as Jesus used it, means the generation of mankind living contemporaneously with Jesus.
In William F. Arndt and Wilbur Gingrich's lexicon, a Greek-English Lexicon of the New Testament, 1974, the first meaning of genea is "those descended from a common anscestor, a clan, then race, kind," etc. Thayer, in his lexicon, A Greek-English Lexicon of the New Testament, says the meaning of genea is "men of the same stock, a family". The Louw and Nida computerized lexicon says that the word "genea" can be understood as "people of the same kind; successive following generations...descendants". The understanding of these lexical references is that the word "genea" can also have a broader, more extended meaning than the limiting view of simply the current generation living at the time concurrent with the speaker. The context must decide which understanding the author has in mind.
Neil D. Nelson Jr., a doctor of philosophy candidate at Dallas Theological Seminary, in examining Matthew's use of "this generation" in the first gospel, says,
A study of the use of he" genea haute" ["this generation"] (ll:16; 12:41, 42, 45; 23:36; 24:34) and genea with other descriptive adjectives (12:39, 45; 16:4; 17:17) used in the same sense reveals that the kind of people referred to are characterized as those who reject Jesus and his messengers and the salvific message they preach, who remain unbelieving and unrepentant, who actively oppose Jesus and his messengers through testing and persecution, and who will face eschatological judgment. The pejorative adjectives given to "this generation" (evil, adulterous, faithless, perverse; cf. 12:39, 45; 16:4; 17:17) throughout the gospel are qualities that distinguish those who are subjects of the kingdom from those who are not...The opponents of Jesus' disciples in Matthew 24-25 share similar traits with "this generation" as characterized in these...chapters. (Neil D. Nelson, Jr. ""This Generation" In Matt. 24:34; A Literary Critical Perspective", JETS 38:3 September 1995 376)
John Young, in his book, Jesus Did Not Return in A.D. 70, published by Vantage Press, 1999, page 50, concludes, "Considering the uncomplimentary things Jesus said in Matthew 23 about the Jewish leaders, Matthew 24:34 could have been translated: 'Truly I say to you, this KIND [instead of generation] will not pass away until all these things take place.' For the same KIND of people will continue to contradict and oppose Christ's authority until Christ shall have taken the reins of human government." (Emphasis added.)
Clearly, the meaning of "this generation" is not limited in understanding to the generation concurrent with Jesus, nor is it to be understood as referring to disciples of that contemporaneous generation who will see the parousia of Christ.
4) If by the word "generation" Jesus was referring to those who heard Him the day He gave the teaching, He would have in effect been saying that His coming (i.e. His 2nd parousia) would be before the last man of the generation who heard Him that day, died. But, by Jesus' own admission, He did not know "the day or the hour" of His return (Matt. 24:36). A study of the use of the term "hour" reveals that the New Testament writers used it in two distinct ways: (1) in a specific sense, where such words as "the", "one", "third", "very", "dinner", "every", "half an" precede the use of the word. In each case, a definite hour is intended, and (2) in a general sense, where the word "hour" may be understood to be equal to our use of the word "time". A few examples of this usage are: Luke 1:10; 12:40, 12:46; John 2:4; I Cor. 4:11. The phrase, "day or...hour", in the context of the Olivet Discourse (Matt. 24:36), is one that speaks of a general time perspective (following the midpoint of the 70th Week which begins with the abomination of desolation -Matthew 24:15) and is not referring to a specific hour of a 24-hour day nor is the term "day" to be understood as a specific day of the week within the same 70th Week perspective.
It is obvious from His teaching in Matthew 24:45-51, that Jesus was expecting a rather long delay before His return. The "master's" remanstrance with the "evil slave" (24:48) indicates that the delay was of such duration that slothfulness and indolence has set into the fabric of the church. That indication is repeated in the parable of the ten virgins. The delay of the bridegroom's coming was such that the virgins fell asleep (25:5). It hardly seems probable that such a slothfulness had invaded the church to such a marked degree before AD 70. The original apostolic band (except Judas) was still living and ministering. The apostle Paul, actively ministering in the Mediterranean world, including Israel, is supposed to have been martyred somewhere around AD 65, only a few years before the fall of Jerusalem. With such stalwarts of the faith and their immediate disciples still living and ministering, had the church fallen into such dire straits by AD 70 and to such a degree that it was to be characterized as Jesus indicates in the parable? The epistles certainly demonstrate that the church had its growing pains and needs, but had she become delinquint in her service unto the Lord and become unguarded, dull, sluggish and unwary? There is no historical data that would support such a broad scale notion. When the apostle John saw the "great multitude" in Revelation seven, he wondered who they could be. In his short time on earth as a disciple of Jesus, perhaps only 60 years, the gospel had not yet reached "every nation and all tribes and peoples and tongues". That would only come after several centuries of the gospel spreading all over the world.
When Jesus said He did not know the "day and hour", He certainly understood that His second coming would be delayed and that the kinds of behavior he described in the parables following His direct teaching in Matthew 24:3-31 would invade the church in general. Although Christ did not know the "hour" (when in history, not the general timeframe within the 70th Week) of His return, as He said (Matt. 24:36), it is clear that He didn't expect to come within the next 40 years (by AD 70) or even within the generation that heard Him that day.