The book of Daniel records a series of events during the last seven years before Jesus returns. Many refer to this as the 70th week of Daniel or the Tribulation. It ends with the return of Jesus and the beginning of a thousand year reign of Christ on this earth.
That final seven years begins with a peace treaty between Israel and many other nations. This treaty is broken after three and a half years by a world leader who causes the sacrifices and offerings of the temple to stop and replaces them with rituals that will be viewed by the Jews as an "abomination".
"He will confirm a covenant with many for one ‘seven.’ In the middle of the ‘seven’ he will put an end to sacrifice and offering. And at the temple he will set up an abomination that causes desolation, until the end that is decreed is poured out on him." (Daniel 9:27)
"Now whenever you may be perceiving the abomination of desolation, declared by Daniel the prophet, standing where it must not (let the reader apprehend), then let those in Judea flee into the mountains...for in those days will be affliction such as has not occurred from the beginning of creation which God creates until now." (Mark 13:14-20)
The Jewish Temple in Jerusalem will apparently be rebuilt and the abomination of that future Temple will bring a rebellion by Israel against that world leader bringing upon the Jews the greatest persecution in their long history. The world leader who authorizes the abomination is called a wild beast in the book of Revelation but most scholars today refer to him as the Antichrist. He will have brought peace to the Middle East with the help of another wild beast called the False Prophet. Together they form the final government and religion of this age. For two and a half years after the abomination they will seek to eliminate the Jewish people. However, God will protect Israel and supernaturally pour out His wrath on the kingdom of the Antichrist during the final year of the Tribulation.
Before that one year of wrath comes, all believers killed will be raised to life, and together with the living believers will be "snatched away" through the clouds to meet Jesus in air. They will be transformed into immortals with bodies like Jesus now has. They will reign with Him for one thousand years - called the Millennium by many today.
"For the Lord Himself will descend from heaven with a loud command, with the voice of an archangel, and with the trumpet of God, and the dead in Christ will be the first to rise. At the same time, we who are alive and remain will be snatched away together with them in the clouds to meet the Lord in the air. And so we will always be with the Lord." (1 Thessalonians 4:15-18)
"For God has not appointed us to suffer wrath, but to obtain salvation through our Lord Jesus Christ. He died for us so that whether we are awake or asleep, we may live together with Him. Therefore encourage and build one another up, just as you are already doing." (1 Thessalonians 5:9-11)
"Then I saw heaven standing open, and there before me was a white horse. And its rider is called Faithful and True. With righteousness He judges and wages war. He has eyes like blazing fire, and many royal crowns on His head. He has a name written on Him that only He Himself knows. He is dressed in a robe dipped in blood, and His name is The Word of God. The armies of heaven, dressed in fine linen, white and pure, follow Him on white horses. And from His mouth proceeds a sharp sword with which to strike down the nations, and He will rule them with an iron scepter. He treads the winepress of the fury of the wrath of God the Almighty. And He has a name written on His robe and on His thigh: King of kings and Lord of lords."(Revelation 19:11-16)