Every now and then, someone will ask questions about the timing of Christ's return. Reading the New Testament accounts, there is some question whether Jesus' predictions of the destruction of Jerusalem in 70 A.D. became mixed in with the predictions of his return and of the Last Judgment. After making a series of prophecies, Jesus states, "All this will come upon this generation" (Matthew 23:36), and likewise "this generation will not pass away until all these things have happened" (Matthew 24:34). Some of these prophecies are clearly about the destruction of Jerusalem, which did in fact take place in that generation. Others are often taken to be of the end of the world.
My concern for the moment is not to get to the bottom of that particular question -- whether the other prophecies were about the end of the world -- since I'm not sure it can be definitively answered before the end of the world, by which time the question will be moot. My only point here is to show why I do not think that Jesus taught the Last Judgment would take place during that generation.
In Matthew 23 and Matthew 24, there are a series of predictions bound to that generation. Next, starting at the end of Matthew 24 and through the majority of Matthew 25, there are three parables in a row that point out a long absence waiting for Christ's return: "My master is staying away a long time" (24:48), "The bridegroom was a long time in coming" (25:5), "After a long time the master of those servants returned" (25:19). In fact, the main point of the parable of the ten virgins is that the length of the wait for the bridegroom is so long as to cause trouble among those waiting.
It is only after the three Parables of the Long Absence that we have the teaching of the Last Judgment. That is why I am convinced that Christ did not teach the Last Judgment would take place "in this generation": the records of the prophecies anchored to that generation are separated from the description of the Last Judgment by the Parables of the Long Absence.