Jesus had told his disciples before his arrest that they could well be killed on account of the faith (John 16:2; cf. Acts 7:59; Acts 12:2). He now tells the Christians of Smyrna to “be faithful unto death.” Those last two words, “until death,” indicate that some of these Christians would be brought to death’s door before deliverance came, while others might indeed need to lay down their life for the sake of the gospel.
10 Do not fear what you are about to suffer. Behold, the devil is about to throw some of you into prison, that you may be tested, and for ten days you will have tribulation. Be faithful unto death, and I will give you the crown of life.