Paul reveals God's hidden mystery in Ephesians 3: that Gentiles would become equal heirs with Jews in God's family through Christ. This revolutionary truth broke down the wall of separation that existed in the temple and in society. Paul received this revelation through the Holy Spirit, the same Spirit who helps believers today understand God's truth. Even while imprisoned, Paul saw himself not as a prisoner of circumstances but as a prisoner of Christ, understanding that God uses our trials for eternal purposes. His humility as the least of the apostles shows that God chooses unlikely candidates to display His grace and power.
