When will the end be according to Jesus? Not when you've been told...and yes, it really is specified

When will the end come according to Jesus' speech in Matthew 24, Mark 13 and Luke 21?  The prophesy in those scriptures is often quoted.  Jesus tells of earthquakes, wars, famine, etc as happening right before the end.  When did he prophesy the end would be?  In that speech, he states, 

But of that day or hour no one knows, not even the angels in heaven, nor the Son, but the Father alone.

So far, that's a good argument for saying that we don't know when the end will come.  Except, it's taken out of context of the prophesy.  A few versus prior, Jesus states,

Truly I say to you, this generation will not pass away until all these things take place.

Who is this generation?  Well, we get all kinds of arguments about "which" generation is being spoken about.  But, in context of the scripture itself, we know which generation.  It was the small group of people to which Jesus was speaking.  That group was his disciples who asked him privately about when the end would come.  (Actually, technically, according to Mark, they asked Jesus about the destruction of Jerusalem that he previously mentioned, but Jesus used the opportunity to talk about the end of everything, implying the destruction of Jerusalem was linked to the end of everything; in Matthew, they asked about the end and return of Jesus.)

How do we know that "this generation" applies to the one of which the disciples where apart?  Even within the same speech, Jesus is imploring his disciples to be watchful, that the end could come at any moment.  He doesn't say, "When that generation sees these things, then they should be watchful."  He tells his disciples that he's putting them in charge, and for them to keep alert.

Take heed, keep on the alert; for you do not know when the appointed time will come. It is like a man away on a journey, who upon leaving his house and putting his slaves in charge, assigning to each one his task, also commanded the doorkeeper to stay on the alert.  Therefore, be on the alert--for you do not know when the master of the house is coming, whether in the evening, at midnight, or when the rooster crows, or in the morning-- in case he should come suddenly and find you asleep.

Then Jesus says that all of his followers should be alert.  None of these statements were meant for some future unknown and unspecified generation.  It was a message intended for the disciples to which Jesus was directly speaking.  This prophesy was intended to be fulfilled before their generation passed on.  This means, according to his prophesy (taken in context), the world should have ended sometime in what we now call the 1st Century, just over 1900 years ago.  Well, Jerusalem was sacked (not really destroyed, though the Second Temple was destroyed) in 70 C.E., and the rest of the world is still here.  This isn't a prophesy about the future.  It is a failed prophesy about a time in ancient past.

All scripture quotes in this article are from Mark 13 of the New American Standard Bible via The Unbound Bible.