2 Timothy 2:9

Paul is preaching the gospel and because of that, he is in chains as a criminal. In that time and place, you could very well be thrown into prison for preaching the gospel. I don't know about it happening in North America nowadays, but there are parts of the world where that still happens. There certainly is persecution and a tough life for all Christians, but not necessarily imprisonment. What's interesting here is that Paul talks about being in chains and then contrasts that to the word of God, which is not bound. Paul may be in prison, but that cannot happen to the word of God. In the book of Acts, we read about how the Philippian Jailer was converted when Paul and Silas were sent to prison. It's not as if being tied up can restrain the word of God.