“…that I may open my mouth boldly to make known the mystery of the gospel, for which I am an ambassador in chains…” (Ephesians 6:19-20).
Being a citizen of a nation does not automatically make you its ambassador. Being a herald of a king is not the same as being his ambassador.
Like the other apostles, Paul was an ambassador of Christ. These citizens of His kingdom and heralds of His gospel were also given unique authority and power because they were His duly authorized ambassadors. Baptized with the Holy Spirit ten days after Jesus’ ascension (Acts 1:3-5), these personal witnesses of Jesus’ resurrection (Acts 1:22, 10:39-40) were gifted in such a way that they were guided into all truth (John 16:13)—the Spirit of truth teaching them all things and bringing to their remembrance all things Jesus said to them (John 14:26). The power to perform miracles by which the Lord could confirm the revelation of His new, better, and final covenant was uniquely endowed upon the apostles, His divinely authorized ambassadors.
Because Jesus’ kingdom is not of this world (John 18:36), His ambassadors were sorely mistreated by the Roman Empire and its emissaries. What indignities were heaped upon Christ’s ambassadors: condemned to death, made a spectacle to the world, dishonored, poorly clothed, beaten, homeless, reviled, persecuted, defamed, made as the filth of the world, the offscouring of all things until now (1 Corinthians 4:9-13). Rather than being treated with respect and allowed the courtesy to move about freely as an ambassador of the King of kings and Lord of lords, the apostle Paul arrived in Rome under arrest and in chains.
Because of these ambassadors and their fidelity to their duties in Christ’s kingdom, it is possible for you to no longer be a stranger and foreigner in God’s world but a fellow citizen with the saints and a member of the family of God (Ephesians 2:19-20).