Acts 25.25 (NIV)

Then someone came and said, “Look! The men you put in jail are standing in the temple courts teaching the people.”

As Paul will write later, even when men are put into prison for preaching the gospel, the Word of God is not imprisoned.  Here the disciples are thrown into prison on the Temple Mount.  The next day they are in the temple preaching away as if nothing ever happened.  The men who threw them into prison go and unlock the prison and…nothing there! It’s funny that, in their investigation of the incident, the Sanhedrin doesn’t ask how the men got out of prison, but why they keep on preaching in Jesus name!
We must not make the error of assuming that when e powers that be throw us into prison because we preach the gospel, that the gospel itself is hindered.  It is not hindered, indeed it is never hindered by mere concrete and walls.  May we preach despite opposition and rough the inevitable stumblingblocks that Satan throws in our path.