Fear none of those things which thou shalt suffer: behold, the devil shall cast some of you into prison, that ye may be tried; and ye shall have tribulation ten days: be thou faithful unto death, and I will give thee a crown of life.
We are not to fear anything that may cause us to suffer. Some will suffer by being cast into prison, for the purpose of being tried for their faith. Even if faced with death, they are to be faithful to their faith in Christ. If they do, they will receive the crown of life, which is a special reward for martyrs.