Why did God raise up the Apostle Paul and start calling out the Body of Christ?

Les explains that after Israel crucified their Messiah and Peter did not succeed in turning Israel to repentance, God brought up the Apostle Paul and began calling out the Body of Christ, primarily from among the Gentiles. This calling has nothing to do with the Old Testament program or the tribulation, because that is tied primarily to the Jew. The Body of Christ is insulated from God's dealings with Israel either before or after, so it has to be off the scene before God can pick up dealing with Israel. Les teaches that this is why he teaches the Rapture. If the Church were removed, the Old Testament economy of the coming Messiah, tribulation, King, and Kingdom would resume. But when Israel rejected it, God went to the calling out of the Body of Christ, which must be raptured, and then He will yet bring in the tribulation to Israel. Romans 11:25 is maintained as the triggering mechanism for Christ's coming for the Church.