If you read this closely, you will understand that Jesus is telling them this before he is crucified.  None of the prophets had been told the exact time of His 1st coming: the time that he would pay the price for their sins.  That was the time of Jacobs great troubles.  Daniel was told to seal up his knowledge until the end [Dan 12]: the end being when he brought them Salvation.  This knowledge made him sick.
 
        Only a very few of the Jews accepted Jesus as their Messiah.  They were looking for him at that time but without an exact year or date to help them.  It was the priest and Pharisees that crucified him, the government/Sanhedrin.  They rejected Jesus and he rejected them.  This is why he said that if he hadn't come early no one would be saved because then the priests would have accepted him, if they had known the precise timing.
 
        He had to die and his own received him not.  Those 70 weeks of Daniel 9 were completed at Pentecost when the Holy Spirit came and dwelt in those 120 in the Upper Room. The Temple was destroyed 40 years later.
 
        He talks about the very end of time and what will happen after the Temple is destroyed. Almost 2,000 more years come after that, and he said He would come back and this worn out world would be burned up.  Malachi and Peter tell us about that.  John tells us of the New Jerusalem coming down.  Even Enoch tells us about the coming of the New Jerusalem and gives a particular date on the Hebrew calendar.  Most surprising to me.
 
Matthew 24:1-9, 15-22
    And Jesus went out, and departed from the temple: and his disciples came to him for to shew him the buildings of the temple. [2] And Jesus said unto them, See ye not all these things? verily I say unto you, There shall not be left here one stone upon another, that shall not be thrown down.
        (Then He tells about the end of the world.)

    [3] And as he sat upon the mount of Olives, the disciples came unto him privately, saying, Tell us, when shall these things be? and what shall be the sign of thy coming, and of the end of the world?
    [4] And Jesus answered and said unto them, Take heed that no man deceive you. [5] For many shall come in my name, saying, I am Christ; and shall deceive many. [6] And ye shall hear of wars and rumours of wars: see that ye be not troubled: for all these things must come to pass, but the end is not yet.
    [7] For nation shall rise against nation, and kingdom against kingdom: and there shall be famines, and pestilences, and earthquakes, in divers places. [8] All these are the beginning of sorrows. [9] Then shall they deliver you up to be afflicted, and shall kill you: and ye shall be hated of all nations for my name's sake.
   
    (This is the tribulation of the saints/Christians/believer's in Christ as Messiah)
 
    15 When ye therefore shall see the abomination of desolation, spoken of by Daniel the prophet, stand in the holy place, (whoso readeth, let him understand:)
   
        (I hate to says this but I believe that this is the priest who stands up in the temple after he crucifies Jesus and takes his place again as high priest. Jesus is now our high priest.)
 
    [16] Then let them which be in Judaea flee into the mountains: [17] Let him which is on the housetop not come down to take any thing out of his house: [18] Neither let him which is in the field return back to take his clothes. [19] And woe unto them that are with child, and to them that give suck in those days! [20] But pray ye that your flight be not in the winter, neither on the Sabbath day: [21] For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be.
 
        (The Temple was destroyed in the middle of summer/9th of Av.  The Jews fought the Romans.  They didn't like being told what to do in their own country.  Jerusalem was to always belong to them. But they had been removed to Babylon in the time of Nebuchadnezzar for 70 years.  God punishes his people [Jew and Christian] in order to bring them back to him.  Make them cry out to Him for salvation/help. He promises to answer that cry.)
 
[22] And except those days should be shortened, there should no flesh be saved: but for the elect's sake those days shall be shortened.
   
        (So Jesus came early.  He's coming again at an appointed time.  Enoch gave a date, but what is the year?
 
        God gave mankind 120 years [Gen 6:3]: Jubilee years or 6000 years.  When did he start counting those years? Well, the Book of Jubilees says that Adam was in the garden for exactly 7 years when he sinned and was put out of the garden on the 17th day of the 4th month of the 8th year.
 
        Enoch explained our calendar and said it was 364 days long but since then it is now 36 hours or 1 day and a quarter have been added making 365.25.  If you can figure it out give me a call.)
 
        I'm looking at that one particular star that shines down that well at midnight on January 11, 2013.  "I may be wrong but again I may be right."  "I'm lookin for Jesus to return, Hallelluyah!"
 
        Sorry that this was so long.  I get carried away sometimes.  This has been a 50-year study.  So its a Jubilee year!!!! for me.
 
May God bless you, jfh