What must the Jews go through before enjoying the blessings of Christ's return?
The Jewish people must pass through the seven-year Tribulation before they enter the blessings of Christ's return. Once the Church is raptured and the fullness of the Gentiles is complete, God turns again to Israel. During that seven-year period, their blindness falls away, and God deals with Israel.
Les explains that after the Church is completed and raptured, God will turn back to the Jew. The Jewish people must go through the seven years of tribulation, which is predominantly the time God starts dealing with Israel. Only after that tribulation will they enjoy all the blessings of Christ's return. He also notes from II Thessalonians chapter 2 that as soon as the Church is gone, the Antichrist appears and the world enters that seven-year period. During this time, Israel's blindness falls away.
For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fulness of the Gentiles be come in.