There is no difference between a Jew sanctified by the Spirit and by faith in Christ, and a gentile sanctified by the Spirit and by faith in Christ. None whatsoever:
Yes there is, a person's faith produces grace from God. Many of those churches 2,000 years ago produced false prophets and teachers who were not born again.
2 Peter 2:1-3 But there were also false prophets among the people, just as there will be false teachers among you. They will secretly introduce destructive heresies, even denying the sovereign Lord who bought them—bringing swift destruction on themselves. 2Many will follow their depraved conduct and will bring the way of truth into disrepute. 3In their greed these teachers will exploit you with fabricated stories. Their condemnation has long been hanging over them, and their destruction has not been sleeping.