These three accounts are concerning the same discourse by Jesus spoken on the same day and time. This is known because in the Mark account at the end of chapter 12 it tells of Jesus' teaching concerning the poor widow woman giving her last coins, and Luke begins with the same event about the poor widow woman giving her last coins. From the temple they then journeyed up the Mount of Olives and when four apostles were able to speak to Jesus privately, they asked Him about what He had said about the destruction of Herod's beautiful temple buildings.

Mar 12:41 And Jesus sat over against the treasury, and beheld how the people cast money into the treasury: and many that were rich cast in much.
Mar 12:42 And there came a certain poor widow, and she threw in two mites, which make a farthing.
Mar 12:43 And he called [unto him] his disciples, and saith unto them, Verily I say unto you, That this poor widow hath cast more in, than all they which have cast into the treasury:
Mar 12:44 For all [they] did cast in of their abundance; but she of her want did cast in all that she had, [even] all her living.

Luk 21:1 And he looked up, and saw the rich men casting their gifts into the treasury.
Luk 21:2 And he saw also a certain poor widow casting in thither two mites.
Luk 21:3 And he said, Of a truth I say unto you, that this poor widow hath cast in more than they all:
Luk 21:4 For all these have of their abundance cast in unto the offerings of God: but she of her penury hath cast in all the living that she had.

This shows us that Luke is telling the same order of events as the other two are.

Mat 24:1 Jesus came out from the temple and was going away when His disciples came up to point out the temple buildings to Him.
Mar 13:1 As He was going out of the temple, one of His disciples *said to Him, "Teacher, behold what wonderful stones and what wonderful buildings!"
Luk 21:5 And while some were talking about the temple, that it was adorned with beautiful stones and votive gifts, He said,

Mat 24:2 And He said to them, "Do you not see all these things? Truly I say to you, not one stone here will be left upon another, which will not be torn down."
Mar 13:2 And Jesus said to him, "Do you see these great buildings? Not one stone will be left upon another which will not be torn down."
Luk 21:6 "{As for} these things which you are looking at, the days will come in which there will not be left one stone upon another which will not be torn down."

Mark and Matthew make it clear that Jesus and followers had left the temple complex when some remarked about the beauty of the the Herod buildings that they were viewing.   And that is the keywords "These great building!"  It is those Herod built buildings being destroyed that prompts the disciples want to know WHEN those building will be destroyed! When will these Herod buildings be destroyed until not one stone lay upon another?
 

Mat 24:3 As He was sitting on the Mount of Olives, the disciples came to Him privately, saying, "Tell us, when will these things happen, and what {will be} the sign of Your coming, and of the end of the age?"
Mar 13:3 As He was sitting on the Mount of Olives opposite the temple, Peter and James and John and Andrew were questioning Him privately, :4 "Tell us, when will these things be, and what {will be} the sign when all these things are going to be fulfilled?"
Luk 21:7 They questioned Him, saying, "Teacher, when therefore will these things happen? And what {will be} the sign when these things are about to take place?"
 

 They asked when the temple buildings would be destroyed,  but they also asked what would be the signs of His coming and what signs to look for concerning the coming of the end of the age.  For they believed at that time that Jesus would return and set up the New Kingdom after the destruction of the Herod Temple.

The Olivet discourse wasn't a speech made to the multitudes.  He was speaking with four of the twelve disciples in private.

Jesus was speaking about what it will be like the end of the age when false Christs saying I am He (Jesus).  But don't believe or follow them.

Mat 24:4 And Jesus answered and said unto them, Take heed that no man deceive you.
Mar 13:5 And Jesus answering them began to say, Take heed lest any [man] deceive you:
Luk 21:8a And he said, Take heed that ye be not deceived:

Mat 24:5 For many shall come in my name, saying, I am Christ; and shall deceive many.
Mar 13:6 For many shall come in my name, saying, I am [Christ]; and shall deceive many.
Luk 21:8b And He said, "See to it that you are not misled; for many will come in My name, saying, 'I am {He,}' and, 'The time is near.' Do not go after them.

Then He begins to speak about those things that will happen soon and warns them that they are not to think the end will come when they hear of these events.

Mat 24:6 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.
Mar 13:7 And when ye shall hear of wars and rumours of wars, be ye not troubled: for [such things] must needs be; but the end [shall] not [be] yet.
Luk 21:9 But when ye shall hear of wars and commotions, be not terrified: for these things must first come to pass; but the end [is] not by and by.

These wars and rumors of wars are not signs of the end of the age or His return, but there will be distinct signs that they are to look for when He is about to return, which Jesus calls sorrows or birth pangs that will happen before the birth of the new age.

Mat 24:7 For nation shall rise against nation, and kingdom against kingdom: and there shall be famines, and pestilences, and earthquakes, in divers places.
Mar 13:8a For nation shall rise against nation, and kingdom against kingdom: and there shall be earthquakes in divers places, and there shall be famines and troubles:
Luk 21:10 Then said he unto them, Nation shall rise against nation, and kingdom against kingdom: And great earthquakes shall be in divers places, and famines, and pestilences; and fearful sights and great signs shall there be from heaven.

Mat 24:8 All these [are] the beginning of sorrows.
Mar 13:8b these [are] the beginnings of sorrows.
Luk 21:12 But before all these,

When Luke says "But before all these" it is the same as the other two saying they are the birth pangs.   Luke understanding that the beginning of sorrows are the calamities that precede the final days.

NOTE: according to the Blue Letter Bible on line: "sorrows" is referring to
2) intolerable anguish, in reference to the dire calamities precede the advent of the Messiah.
 
 
 

So after they hear of wars and rumors of wars, and are told the time is not yet,  then these things will begin to happen;

Mat 24:9 "Then they will deliver you to tribulation, and will kill you, and you will be hated by all nations because of My name.
Mar 13:9 "But be on your guard; for they will deliver you to {the} courts, and you will be flogged in {the} synagogues, and you will stand before governors and kings for My sake, as a testimony to them.
Luk 21:12 "But before all these things, they will lay their hands on you and will persecute you, delivering you to the synagogues and prisons, bringing you before kings and governors for My name's sake.

Mar 13:10 "The gospel must first be preached to all the nations.
Luk 21:13 "It will lead to an opportunity for your testimony. (:14) "So make up your minds not to prepare beforehand to defend yourselves; (:15) for I will give you utterance and wisdom which none of your opponents will be able to resist or refute.

Mat 24:10 "At that time many will fall away and will betray one another and hate one another.
Mar 13:12 "Brother will betray brother to death, and a father {his} child; and children will rise up against parents and have them put to death.
Luk 21:16 "But you will be betrayed even by parents and brothers and relatives and friends, and they will put {some} of you to death,

Mat 24:11-13 "Many false prophets will arise and will mislead many. (:12) "Because lawlessness is increased, most people's love will grow cold. (:13) "But the one who endures to the end, he will be saved.
Mar 13:13 "You will be hated by all because of My name, but the one who endures to the end, he will be saved.
Luk 21:17 and you will be hated by all because of My name. (:18) "Yet not a hair of your head will perish. (:19) "By your endurance you will gain your lives.

Mat 24:14 "This gospel of the kingdom shall be preached in the whole world as a testimony to all the nations, and then the end will come.

Jesus is speaking of events that will take place over the next 40 years until the destruction of the Herod buildings will take place.  During this time Paul will bring the gospel to the gentiles. And the word will reach the known world of that time.
 

Note: Some believe that ALL of Matt 24 is going to take place in the last 7 years of this age, but Jesus is speaking about the Herod Temple.  The reason the Romans took the temple and all the buildings down stone by stone was to retrieve the gold that had melted and run into the cracks between and under the stones.
 

In the next section, we read of the Abomination of Desolation, this abomination to God in the Temple will be the cause the desolation of not only those Herod built buildings,  but also of the entire city of Jerusalem.
 

Mat 24:15 "Therefore when you see the ABOMINATION OF DESOLATION which was spoken of through Daniel the prophet, standing in the holy place (let the reader understand),
Mar 13:14a "But when you see the ABOMINATION OF DESOLATION standing where it should not be (let the reader understand),
Luk 21:20 "But when you see Jerusalem surrounded by armies, then recognize that her *desolation is near.

****Notice this does not talk of the polluting of the Holy City as in Dan 11:31 but of the desolation told of in Dan 9:26. The Abomination of desolation happened in 70 AD with the complete desolation of the Temple.

Mat 24:16 then those who are in Judea must flee to the mountains.
Mar 13:14b then those who are in Judea must flee to the mountains.
Luk 21:21a "Then those who are in Judea must flee to the mountains,

Mat 24:17 "Whoever is on the housetop must not go down to get the things out that are in his house. (:18) "Whoever is in the field must not turn back to get his cloak.
Mar 13:15 "The one who is on the housetop must not go down, or go in to get anything out of his house; (:16) and the one who is in the field must not turn back to get his coat.
Luk 21:21b and those who are in the midst of the city must leave, and those who are in the country must not enter the city; :22 because these are days of vengeance, so that all things which are written will be fulfilled.

They must flee because the city and temple are going to be totally destroyed. Left desolate, laid even to the ground as Jesus said while weeping over the city.

Mat 24:19 "But woe to those who are pregnant and to those who are nursing babies in those days! (:20) "But pray that your flight will not be in the winter, or on a Sabbath.
Mar 13:17 "But woe to those who are pregnant and to those who are nursing babies in those days! (:18) "But pray that it may not happen in the winter.
Luk 21:23a "Woe to those who are pregnant and to those who are nursing babies in those days;

The below verses are speaking of the destruction of the Holy City.

Mat 24:21 "For then there will be a great tribulation, such as has not occurred since the beginning of the world until now, nor ever will.
Mar 13:19 "For those days will be a {time of} tribulation such as has not occurred since the beginning of the creation which God created until now, and never will.
Luk 21:23b for there will be great distress upon the land and wrath to this people; (:24) and they will fall by the edge of the sword, and will be led captive into all the nations; and Jerusalem will be trampled under foot by the Gentiles until the times of the Gentiles are fulfilled.

Mat 24:22 "Unless those days had been cut short, no life would have been saved; but for the sake of the elect those days will be cut short.
Mar 13:20 "Unless the Lord had shortened {those} days, no life would have been saved; but for the sake of the elect, whom He chose, He shortened the days.
 
 

Luke has just made it VERY clear that the great tribulation begins when Jerusalem falls because that is when the Jews were carried into the nations,  and also lets the reader  know that this tribulation will not end until the time of the Gentile is complete! This particular Great Tribulation is the Great distress upon the land (Jerusalem) and this people (the Jews). It begins the longest exile even know to the Jews.   Not that there won't be a great tribulation in the end days also.

 History tells us that the Zealots, that the Romans were chasing down, fled to Jerusalem and begged to be let in.  General Vespersian was at their heels. He surrounded Jerusalem with his armies. Inside Jerusalem the Zealots took the temple and set up the abomination which was a false High Priest in the temple.  But then for some reason the general withdrew his armies. This gave all that would heed Jesus warning to flea out of the city to do so.  Within the month Titus returned with his armies and destroyed not only the temple but also the Holy City and killed over a million Jews and carried the rest of the population of Jerusalem captive into the nations. This was documented by Joseph Flavius in  "The Jewish Wars, Book IV chap 3"  And should be read by any serious student of prophecy.
 

I believe the time of the gentiles trampling down Jerusalem came to an end when the Jews recaptured Jerusalem in 1967.   "and Jerusalem will be trampled under foot by the Gentiles until the times of the Gentiles are fulfilled.
Note; This isn't speaking of the time of the gentiles spoken of by Paul.  Paul is speaking spiritually and is in reference to the the Jewish nation becoming last, while the Gentiles will be first to receive the gospel and accept the Messiah.  That time of the gentile will not end until the resurrection/rapture.
 

Now we must go back and look at Daniel to see more about these days of vengeance Luke spoke of, and what Jesus said would happen to the Temple (not one stone left upon another) during the time of vengeance.

Daniel 9:26 tells us that a prince will come and his people will destroy not only the temple/sanctuary to a complete destruction, but also the city of Jerusalem.

Don't look back to Daniel 11:31 because those verses are not about total destruction as in "Not one stone will remain upon another", but tells of a desecration of the Holy fortress, a pollution of the Holy City. (see; The King of the North link on this web site)

History tells us that Titus came and his people totally destroyed the Temple/sanctuary and the Holy City to a complete destruction.
Archeologists have found a pile of stones from the Temple that were thrown down as the temple was disassembled.
 

At this point the first question "Teacher, when therefore will these things happen? "asked by the disciples, concerning the destruction of the Temple, has been answered......but Jesus, knowing that the second question, and what {will be} the sign of Your coming, and of the end of the age?" that the disciples thought would follow immediately after the destruction.

The days of sorrow that Jesus began the discourse with, will begin the end of days for us some 2000 years later. They are the birth pangs of the end of the age. They are the same as the  4th seal in the book of Revelation.

This is where the text concerning the 'beginning of Sorrows' fits into the time-line of events.

Mat 24:23 "Then if anyone says to you, 'Behold, here is the Christ,' or 'There {He is,}' do not believe {him.} (:24) "For false Christs and false prophets will arise and will show great signs and wonders, so as to mislead, if possible, even the elect.
Mat 24:25 "Behold, I have told you in advance.

Mar 13:21 "And then if anyone says to you, 'Behold, here is the Christ'; or, 'Behold, {He is} there'; do not believe {him;} (:22) for false Christs and false prophets will arise, and will show signs and wonders, in order to lead astray, if possible, the elect.
Mar 13:23 "But take heed; behold, I have told you everything in advance.

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"behold, I have told you beforehand".  In Greek it is idouproereo humin

idou (look or see), proereo (I have said this previously) humin ([to] you.)

proereo {pro-er-eh'-o}

1) to say before a) to say in what precedes, to say above
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In other words, I have told you about this part already. He told of the false Christ and  the beginning of sorrows when He first began the discourse. Remember, Luke said "But before these things", meaning these other things will come first and then the 'beginning of sorrows' (birth pangs) will take place................... before the end of the age and My return.

So let's look at what Mark wrote about the days of the beginning of sorrows, the birth pangs ushering in the end of this age.

Mar 13:5 And Jesus answering them began to say, Take heed lest any [man] deceive you: (:6) For many shall come in my name, saying, I am [Christ]; and shall deceive many.

(:8) For nation shall rise against nation, and kingdom against kingdom: and there shall be earthquakes in divers places, and there shall be famines and troubles: these [are] the beginnings of sorrows.

He goes on to say that we are not to look in the desert or the upper room for Him, but to the sky where we will see Him returning on the clouds to gather the elect (believers).

Mat 24:27 "For just as the lightning comes from the east and flashes even to the west, so will the coming of the Son of Man be.
(:28) "Wherever the corpse is, there the vultures will gather."

Note: In another part of Luke he says the apostles asked where Lord? meaning where should we gather so the angels can find us.  Jesus answers  Wherever the corpse is, there the vultures will gather.  In other words the angels will find you where ever you are.     The eagle/vulture is symbolic of the angels that will do the gathering. This is the day of the resurrection of the dead and the rapture (catching up) of the living IN CHRIST.
 

Mat 24:29 "But immediately after the tribulation of those days THE SUN WILL BE DARKENED, AND THE MOON WILL NOT GIVE ITS LIGHT, AND THE STARS WILL FALL from the sky, and the powers of the heavens will be shaken.
Mar 13:24 "But in those days, after that tribulation, THE SUN WILL BE DARKENED AND THE MOON WILL NOT GIVE ITS LIGHT, (:25) AND THE STARS WILL BE FALLING from heaven, and the powers that are in the heavens will be shaken.
Luk 21:25 "There will be SIGNS IN THE MOON AND THE STARS, and on the earth dismay among nations, in perplexity at the roaring of the sea and the waves, (:26) men fainting from fear and the expectation of the things which are coming upon the world; for the powers of the heavens will be shaken.

(Note: Also see Revelation 6, the 6th seal, for this same event)

So what did Jesus mean when He said "immediately after the tribulation of those days"?
I believe this is referring to the birth pangs as that time of that tribulation.These birth pangs appear to be the same as the 4th seal. For nation shall rise against nation, and kingdom against kingdom: and there shall be famines, and pestilences, and earthquakes, in divers places.  In the 4th seal of Revelation.  It sounds like WWIII when 1/4 of nations of the world will be involved. The rider Death will use war,  famine and disease, which war causes, and the beasts of the earth ( these are the beast seen in Rev 13) to kill.  This to me is also the Gog war.

These signs that follow  in both the Olivet discourse and in the book of Revelation in the 6th seal, I believe are caused by Nuclear weapons going off in the middle east.  The sun and moon are darkened by the thick debris in the air. The sun is like sackcloth nd yet the moon (a lesser light) appears as red and not black, which means by night fall there is less debris in the atmosphere blocking the light of the moon. The mountains shake out of there place like an earthquake. The stars appear to be falling from the sky, but I think these are actually bombs of war.

Mat 24:30 "And then the sign of the Son of Man will appear in the sky, and then all the tribes of the earth will mourn, and they will see the SON OF MAN COMING ON THE CLOUDS OF THE SKY with power and great glory.
Mar 13:26 "Then they will see THE SON OF MAN COMING IN CLOUDS with great power and glory.
Luk 21:27 "Then they will see THE SON OF MAN COMING IN A CLOUD with power and great glory.

This is explaining to the apostles that the reason they are not to look for Him in an upper room, or out in the desert, is because He will come in the clouds of heaven and all will see Him.  No believer need worry over being in the right place on the day of the resurrection and the gathering of the living believers to Him,  because just as a vulture always finds the corpse, the angels will find us wherever, in heaven or earth, we are.

Mat 24:31 "And He will send forth His angels with A GREAT TRUMPET and THEY WILL GATHER TOGETHER His elect from the four winds, from one end of the sky to the other.
Mar 13:27 "And then He will send forth the angels, and will gather together His elect from the four winds, from the farthest end of the earth to the farthest end of heaven.
Luk 21:28 "But when these things begin to take place, straighten up and lift up your heads, because your redemption is drawing near."
 
 

Luke had talked of the time of the end and Jesus' return once before.

Luk 17:22 And He said to the disciples, "The days will come when you will long to see one of the days of the Son of Man, and you will not see it. (:23) "They will say to you, 'Look there! Look here!' Do not go away, and do not run after {them.}
Luk 17:24 "For just like the lightning, when it flashes out of one part of the sky, shines to the other part of the sky, so will the Son of Man be in His day.
Luk 17:25 "But first He must suffer many things and be rejected by this generation.
Luk 17:26 "And just as it happened in the days of Noah, so it will be also in the days of the Son of Man:
Luk 17:27 they were eating, they were drinking, they were marrying, they were being given in marriage, until the day that Noah entered the ark, and the flood came and destroyed them all.
Luk 17:28 "It was the same as happened in the days of Lot: they were eating, they were drinking, they were buying, they were selling, they were planting, they were building;
Luk 17:29 but on the day that Lot went out from Sodom it rained fire and brimstone from heaven and destroyed them all.

Luk 17:30 "It will be just the same on the day that the Son of Man is revealed.
Luk 17:31 "On that day, the one who is on the housetop and whose goods are in the house must not go down to take them out; and likewise the one who is in the field must not turn back.
Luk 17:32 "Remember Lot's wife.
Luk 17:33 "Whoever seeks to keep his life will lose it, and whoever loses {his life} will preserve it.
Luk 17:34 "I tell you, on that night there will be two in one bed; one will be taken and the other will be left.
Luk 17:35 "There will be two women grinding at the same place; one will be taken and the other will be left.
Luk 17:36 ["Two men will be in the field; one will be taken and the other will be left."]

Luk 17:37 And answering they *said to Him, "Where, Lord?" And He said to them, "Where the body {is,} there also the vultures will be gathered."

This is speaking of the resurrection of the dead and the rapture of the living.
 

God bless