Paul and Timothy see their chains as chains for Christ because it gives them a chance to let the Jesus-love inside of them overflow more and more towards those imprisoning them.
There’s more to this life than meets the eye and seeking out pleasure isn’t going to make you feel any less empty inside, and trying to pretend that we can ignore shortcomings in the world around us wont make them go away. It’s Resurrection that gives us hope.
Instead of running, they put aside their freedom knowing that even behind bars they’re free with Jesus and with this the Jailor realizes he needs some of that too.