Throughout my life, I have heard many sermons upon the return of Christ.
Within many, I heard statements such as, “the Lord could come back at any time...”
Yet, the longing for the “long expected” Redeemer has not rushed the Savior’s return. Human efforts to encourage and promote by work of sword or utopia have failed to bring the Lord.
I heard, in the last 30 years or more, a rising cry of mockery fulfilling the prophecy, “Where is the promise of his coming....”.
So what is preventing the return?
Hint: Revelation 6.
Anyone find another place of answer? There is.
The clear answer is given by Jesus himself in his Olivet prophecy -
Mat. 24:1 Then Jesus went out and departed from the temple, and His disciples came up to show Him the buildings of the temple. 2 And Jesus said to them, “Do you not see all these things? Assuredly, I say to you, not one stone shall be left here upon another, that shall not be thrown down.”
3 Now as He sat on the Mount of Olives, the disciples came to Him privately, saying, “Tell us, when will these things be? And what will be the sign of Your coming, and of the end of the age?”
4 And Jesus answered and said to them: “Take heed that no one deceives you. 5 For many will come in My name, saying, ‘I am the Christ,’ and will deceive many. 6 And you will hear of wars and rumors of wars. See that you are not troubled; for all these things must come to pass, but the end is not yet. 7 For nation will rise against nation, and kingdom against kingdom. And there will be famines, pestilences, and earthquakes in various places. 8 All these are the beginning of sorrows.
The end is in stages - Jesus is here prophesying the destruction of the temple in a time of war & trouble. The temple was of no significance after Jesus finishes his work of redemption at Calvary but God allowed it to continue as a centre for Gospel preaching as recorded in Acts. The disciples' question does not imply an understanding of what they were asking.
He gives detailed warnings concerning when the believers should leave the city before the final siege -
15 “Therefore when you see the ‘abomination of desolation,’ spoken of by Daniel the prophet, standing in the holy place” (whoever reads, let him understand), 16 “then let those who are in Judea flee to the mountains.
.....
28 For wherever the carcass is, there the eagles will be gathered together.
Compare with Luke to find that the abomination is the Roman armies - with eagle standards.
Luke 21:20
“But when you see Jerusalem surrounded by armies, then know that its desolation is near. 21 “Then let those who are in Judea flee to the mountains, let those who are in the midst of her depart, and let not those who are in the country enter her.
22 “For these are the days of vengeance, that all things which are written may be fulfilled.
All that was to occur in the lifetime of "this generation."
Mat. 24:32 “Now learn this parable from the fig tree: When its branch has already become tender and puts forth leaves, you know that summer is near. 33 So you also, when you see all these things, know that it[fn] is near—at the doors! 34 Assuredly, I say to you, this generation will by no means pass away till all these things take place.
Having given many details so they would know the end of "this generation" together with the destruction of temple & Jerusalem - all the physical signs of the Old Covenant, Jesus goes on to speak of another end - of heaven & earth.
35 Heaven and earth will pass away, but My words will by no means pass away.
36 “But of that day and hour no one knows, not even the angels of heaven,[fn] but My Father only.
Jesus instruction to believers concerning that event is -
42 Watch therefore, for you do not know what hour[fn] your Lord is coming. 43 But know this, that if the master of the house had known what hour the thief would come, he would have watched and not allowed his house to be broken into. 44 Therefore you also be ready, for the Son of Man is coming at an hour you do not expect.
The timing of the passing away of heaven & earth is in God's and specific warning signs are not given. I suggest we can infer from the warnings Jesus gives that there will be increasing trouble, wickedness & war as the end approaches.
Be ready, watch & pray - & witness to a lost world.