What does the great earthquake at the midpoint set in motion?
The great earthquake at the midpoint of the tribulation triggers or sets in motion the final events of that last three and a half years. It follows the Antichrist's defilement of the temple and the persecution of the Jews, and it precedes Christ's return to the Mount of Olives and His kingdom.
Les explains that at the midpoint, after the two witnesses are resurrected and ascend back into heaven, the Antichrist comes to the temple, defiles it, and forces the Jew to stop their temple worship and worship him instead. This triggers awful persecution on the Jew in that final three and a half years. Les also points out that another big event at the very midpoint is a tremendous earthquake, found in Revelation chapter 6 and again in chapter 11. That great earthquake will trigger or set in motion the final events of that last three and a half years. After that runs its course, Christ returns to the Mount of Olives, sets up His Kingdom, the curse is lifted, and Israel becomes the top nation of the nations, with the rest of the world coming under the blessings of the covenant given to Abraham.