Why did Gentiles have to wait until the cross was finished before the Gospel could be preached to them?
Gentiles had to wait because the Gospel for them depended on Christ’s finished work at the cross—His death, burial, and resurrection. Until that completed work could be presented as a Gospel, Gentiles were not the primary focus; afterward, through Paul’s ministry, the Gospel of God’s grace went out to them.
Les teaches from Acts 9 that the Lord was speaking of His own death, burial, and resurrection, and that Gentiles would have to wait until that finished work of the cross could be presented as a Gospel for them. He notes that before this, the program was Jew only, with some Gentile adherents, but after Paul’s three-year seminary training in the desert, the Gospel of the Grace of God came out. This was not limited to Gentiles, yet it was mostly Gentile. God was now pulling out another group called the Church, or the Body of Christ—predominantly Gentiles with some Jewish adherents—rather than the earlier predominantly Jewish body with some Gentile exceptions. So the cross had to be finished first, then the Gospel of Grace could go to Gentiles through Paul.