Being a prisoner may sound negative, but in Paul's mind, it's a blessing and honor. Roman chains cling to him but it's the love of the Lord and the gospel that holds him fast in his faith. He rejoices in this confinement as he celebrates the stewardship graciously given to him by Jesus.
Even in prison, Paul continues to share "insight into the mystery of Christ." Salvation is for all men, including the Gentiles and Paul is proud to be their messenger.