A lot of Christians were expecting to get raptured by the Lord and his second coming before the tribulation are going to get a shock of their lives because he's not going to do it. He himself said so.
He says right here in the 29th verse (of Matthew 24) plain as day.
Matthew 24:29 Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken: 30 And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory. 31 And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other.
And he could have said again: And then he shall send his angels with a great sound of a trumpet. They shall gather together his elect from the four winds from one end of heaven to the other.
That's when Jesus is going to come, after the tribulation it says it is plain as day in the 29th verse. Immediately after the tribulation of those days, he says after the tribulation shall appear the sign of the Son of man in heaven. After the tribulation. Then shall all the tribes of the earth mourn. After the tribulation they shall see the Son of man coming in the clouds of heaven with power and great glory. And after the tribulation he shall send his angels with a great sound of a trumpet and they shall gather together his elect. That's when Jesus is going to come back for his elect to rapture his saints, to gather them together.