God has formed one new body made up of Jew and Gentile, the church of Jesus Christ. Paul expands on that truth in Ephesians 3:1-13. Paul was imprisoned at the time of this writing, on behalf on the Gentiles. Paul’s mission was to testify to the grace of God. The mystery of God’s plan for his people was revealed to him by the Holy Spirit and he spent his life communicating this message. The mystery is that Gentiles were made fellow heirs and partakers of the promise of Christ Jesus through the gospel.