On the 2nd Sunday of Easter, I preached on Acts 5 and John 20. The Acts 5 passage was when Peter and the others were arrested in Jerusalem for preaching the message of the gospel - that He was put to death by the Jews, and God raised Him from the dead. The high priest and the Sadducees were offended and upset with this teaching and therefore commanded the disciples to no longer teach such things. The disciples replied "We must obey God rather than man." They stood strong in front of those who were opposed to the message of the Gospel. They kept proclaiming Jesus Christ in the face of persecution.
Following that sermon, I was asked about an interesting question - the disciples and early Christians did not fear persecution nor went into hiding despite the opposition. What about those in say, the Soviet Union, who went underground to avoid persecution and continued to worship and spread the gospel on the quiet? Were they wrong for doing this? Should they have done like the disciples and faced the persecution?
This is really a moral question. I think that Dieterich Bonhoeffer faced such a question in Nazi Germany. He struggled with joining the resistance against Hitler. He finally decided that he could join in with them - though he did not believe that he would force all people to do the same thing. He left it up to the individual to make that decision for himself/herself.
So it is during times of persecution. There will be those who stand out publicly and take the penalty for acting is such a way. They do it for consciences sake. At the same time, there will be those who do go "underground" and continue to hold firm to their faith. They do it for consciences sake as well. Neither is wrong. They are doing what they believe the Lord would have them do.
Even in the early church, there were times and places where the church did not meet publicly. Instead they were an "underground" church in order to avoid the persecution. There are times to stand out and times to blend into the background.
The joy that we have is that when the Soviet Union broke apart, those underground Christians came out into the public once again, showing that even while communism tried to kill Christianity, the saying the Lord came true - not even the gates of hell itself shall prevail against the Church of God. We praise God for that very fact.
I hope that helps out with the question.