I know the OT saints and the Tribulation saints will be resurrected at the 2nd coming of Christ but why will the Church be resurrected at the rapture and the OT saints still be in the grave?
The Church’s eternal home is the New Jerusalem (Rev. 21:27) which will not be on Earth. We’ll all be taken there to begin our eternal life with the Lord (John 14:2-3). When that happens, dead believers will be given new physical bodies and the bodies of living believers will be changed from mortal to immortal (1 Cor. 15:51-52). Since the Lord promised to rescue living believers from the time of God’s Wrath (1 Thes. 1:10, Rev, 3:10), He has scheduled this to take place before the end times judgment begin.
Israel’s eternal home is in the promised land on Earth (Ezekiel 43:1-7). Israel has not been promised deliverance from the end times judgments but will be purified through them (Jeremiah 30:11). But dead Old Testament believers do not need to be purified. Raising them from the dead to live on Earth just as the end times judgments are beginning wouldn’t make sense. Therefore the Lord will raise them at the time of the 2nd Coming, after the judgments have ended (Daniel 12:2).
Tribulation believers will not come to faith in time for the Rapture, and they won’t be part of the Church. The resurrection of those who die before the 2nd Coming will happen at the same time as Old Testament believers (Rev. 20:4). Surviving tribulation believers will go into the Millennial Kingdom on Earth in their natural bodies. (Matt. 25:31-40)