In Daniel 12:11-12 we are told: "And from the time that the daily sacrifice shall be taken away, and the abomination that maketh desolate set up, there shall be a thousand two hundred and ninety days. Blessed is he that waiteth, and cometh to the thousand three hundred and five and thirty days."
I have not yet heard a concrete explanation of the gap between the 1,290 days and the 1,335 days spoken of here. This variable makes it impossible to predict with certainty the exact time of the Second Coming.
...in Acts 1:7, Jesus told His disciples: "It is not for you to know the times or the seasons, which the Father hath put in his own power." This was certainly true about that generation, since God told Daniel that the understanding of these things was reserved for the people of the time of the end (Daniel 12:9). Yet, when referring to the endtime, Daniel was told: "and none of the wicked shall understand; but the wise shall understand."

When the Apostle Paul spoke about the coming of the Lord in 1 Thessalonians 5:1-5, he said that the day of the Lord would come as a thief in the night. But in verse 4-5 he added, "But ye, brethren, are not in darkness, that that day should overtake you as a thief. Ye are all the children of light, and the children of the day: we are not of the night, nor of darkness." Paul explicitly states that the coming of the Lord would only be a surprise to those living in darkness.

The Bible teaches that the Great Tribulation lasts for three and onehalf years although popular teaching says it will be seven years. While it is true that Daniel's 70th week lasts for seven years, the scripture teaches that only half of that period is what we know as the Great Tribulation. It says that the woman will be persecuted for a time, times, and half a time which equals three and one-half years. How do we know? In Daniel 7:25 it describes the Great Tribulation as time, times and half a time: And he shall speak great words against the most High, and shall wear out the saints of the most High, and think to change times and laws: and they shall be
given into his hand until a time and times and the dividing of time.

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Jesus Predicts the Destruction of the Temple

Destruction of the Temple Foretold
1 Then Jesus went out and departed from the temple, and His disciples came up to show Him the buildings of the temple. 2And 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."

The Signs of the Times and the End of the Age
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?"
4And Jesus answered and said to them: "Take heed that no one deceives you. 5For many will come in My name, saying, "I am the Christ,' and will deceive many. 6And you will hear of wars and rumors of wars. See that you are not troubled; for all F130 these things must come to pass, but the end is not yet. 7For nation will rise against nation, and kingdom against kingdom. And there will be famines, pestilences, F131 and earthquakes in various places. 8All these are the beginning of sorrows.
9"Then they will deliver you up to tribulation and kill you, and you will be hated by all nations for My name's sake. 10And then many will be offended, will betray one another, and will hate one another. 11Then many false prophets will rise up and deceive many. 12And because lawlessness will abound, the love of many will grow cold. 13But he who endures to the end shall be saved. 14And this gospel of the kingdom will be preached in all the world as a witness to all the nations, and then the end will come.

The Great Tribulation
15 "Therefore when you see the "abomination of desolation,' F132 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. 17Let him who is on the housetop not go down to take anything out of his house. 18And let him who is in the field not go back to get his clothes. 19But woe to those who are pregnant and to those who are nursing babies in those days! 20And pray that your flight may not be in winter or on the Sabbath. 21For then there will be great tribulation, such as has not been since the beginning of the world until this time, no, nor ever shall be. 22And unless those days were shortened, no flesh would be saved; but for the elect's sake those days will be shortened.
23"Then if anyone says to you, "Look, here is the Christ!' or "There!' do not believe it. 24For false christs and false prophets will rise and show great signs and wonders to deceive, if possible, even the elect. 25See, I have told you beforehand.
26"Therefore if they say to you, "Look, He is in the desert!' do not go out; or "Look, He is in the inner rooms!' do not believe it. 27For as the lightning comes from the east and flashes to the west, so also will the coming of the Son of Man be. 28For wherever the carcass is, there the eagles will be gathered together.

The Coming of the Son of Man
29 "Immediately after the tribulation of those days the sun will be darkened, and the moon will not give its light; the stars will fall from heaven, and the powers of the heavens will be shaken. 30Then the sign of the Son of Man will appear in heaven, and then all the tribes of the earth will mourn, and they will see the Son of Man coming on the clouds of heaven with power and great glory. 31And He will send His angels with a great sound of a trumpet, and they will gather together His elect from the four winds, from one end of heaven to the other.

The Parable of the Fig Tree
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. 33So you also, when you see all these things, know that it F133 is near--at the doors! 34Assuredly, I say to you, this generation will by no means pass away till all these things take place. 35Heaven and earth will pass away, but My words will by no means pass away.

No One Knows the Day or Hour
36 "But of that day and hour no one knows, not even the angels of heaven, F134 but My Father only. 37But as the days of Noah were, so also will the coming of the Son of Man be. 38For as in the days before the flood, they were eating and drinking, marrying and giving in marriage, until the day that Noah entered the ark, 39and did not know until the flood came and took them all away, so also will the coming of the Son of Man be. 40Then two men will be in the field: one will be taken and the other left. 41Two women will be grinding at the mill: one will be taken and the other left. 42Watch therefore, for you do not know what hour F135 your Lord is coming. 43But 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. 44Therefore you also be ready, for the Son of Man is coming at an hour you do not expect.

The Faithful Servant and the Evil Servant
45 "Who then is a faithful and wise servant, whom his master made ruler over his household, to give them food in due season? 46Blessed is that servant whom his master, when he comes, will find so doing. 47Assuredly, I say to you that he will make him ruler over all his goods. 48But if that evil servant says in his heart, "My master is delaying his coming,' F136 49and begins to beat his fellow servants, and to eat and drink with the drunkards, 50the master of that servant will come on a day when he is not looking for him and at an hour that he is not aware of, 51and will cut him in two and appoint him his portion with the hypocrites. There shall be weeping and gnashing of teeth.

In addition read the book of Daniel and Revelation, you might find a good commentary like at endtime.com...

The Bible prophesies that a world government will be set up prior to the Battle of Armageddon and the Second Coming of Jesus. A world-class politician, referred to in scripture as the Antichrist or the Beast, will reign over that world government for a three and one-half year period immediately before Armageddon (Revelation 13:5, Daniel 7:25). According to Bible prophecy, several things will happen to set the stage for the appearance of the Antichrist. These include the confirming of the Abrahamic covenant by the world community, a war that will kill the third part of men, the building of Israel's Third Temple, and the establishment of a world economic system for controlling people and forcing their obedience to the world government and to the Antichrist

Our only hope is in Christ. You can't get to heaven as you are because your sins have separated you from God (Romans 3:23). That's why God sent his only son to die for the sins of the world, to bridge the gap between God and man (Romans 6:23). If you were good enough to go to heaven on your own merit, Jesus' death, burial and resurrection would have been unnecessary.

If you would like to accept Jesus as Lord pray right now:

Father, I know that I am a sinner and cannot obtain salvation in and of myself. I come to you in the name of Jesus asking that you forgive me of my sins, and to cleanse me from all unrighteousness and guilt. I trust and believe that Jesus died and rose again to pay my sin penalty. I accept this free gift of salvation, and from this day forward, turn my life completely over to the Lord. I thank you and praise you God for giving me a new life in Christ. Amen.