Christ’s Prisoner or Imprisoned for Christ? (2 Timothy 1:8-18)

Paul is detained by Rome because of Christ's gospel. The good news of Christ seems to be halted because Paul is in prison. In fact, there are some who have turned against Paul because of his current circumstances. It would seem that this would deter Paul. He would see his imprisonment as a negative thing. However, he does not see himself as Rome's prisoner, but as Christ's prisoner. How is it a blessing to be Christ's prisoner? How does being Christ's prisoner shift his perspective from being Rome's prisoner?