The Word of God tells us that we are one body in Christ Jesus.
It also tells us that we have been grafted in and that the walls of separation have come down… Eph. 2:11-14
The pretrib view has worked hard to maintain a separation between Israel and the church. Note that the distinction is between Israel and the church and not the Jews and the Gentiles. This separation is directly opposite God’s removal of the wall of separation that He declared through Paul in Eph. 2:11-14. Paul also has informed us that we have been grafted in.
If you believe the pretrib doctrine, you must hold the separation not only of the Jews and the church, but separate the church into the bride of Christ and the tribulation saints. Because the bride is believed to be removed from the tribulation, those who are saved during the tribulation cannot be the bride of Christ. Therefore a separate set of rules and promises fall upon them. One obvious distinction is the promise of being the bride doesn’t apply to them. In fact the promises and distinctions between the two groups are huge. Because the Word never makes the distinction between the two groups of people, great liberties are taken to further the “understanding” of their existence. When this was first explained to me, I was informed that the tribulation saints were not under the blood of Jesus, but rather their martyrdom paid for their price to be in heaven. This is huge and creates a enormous difference between the two groups of people. I must point out that this group of people referred to as tribulation saints are extra-biblical in nature this segregated group is a by-product of the pretrib doctrine.
If you believe that the cross of Christ has indeed produced one body in Christ Jesus that includes all races which is the bride of Christ then you must also believe that the rapture and the second coming are a singular event. This is a biblical doctrine.
If however, you believe that in the separation of Israel and the church and the tribulation saints you can also have a doctrine that separates the rapture from the second coming. This is a doctrine of man.