A person's silence could possibly indicate his willingness to be a martyr. This would be the case only if his motivation for being silent is to hold to his beliefs regardless of the possibility of being killed for it. In our judgments regarding people's actions, it is best to give the benefit of the doubt from the outset. We should not doubt that a person's actions are virtuous unless all doubt is removed. Motivation is the important question. Unless we know with certainty that a person's motives are corrupt we should refrain from harsh judgment upon them for their actions.
The first three chapters of the book of Job record the devastating circumstances Job endured and his subsequent silence. They indicate that he had experienced great hurt and loss and was suffering, but was handling it correctly. His friends who initially came to comfort him only aggravated his condition by jumping to false conclusions.
But now it is come upon thee, and thou faintest; it toucheth thee, and thou art troubled. Remember, I pray thee, who ever perished, being innocent? or where were the righteous cut off? Job 4:5,7
In actuality, Job had not fainted and was not perishing. Job’s friends read into outward appearances and saw something that wasn’t actually there. They remained so convinced in their false perception that their discourse eventually became a point of concern, resulting in Job praying for them and helping them regain an assured outlook and perspective.
...my servant Job shall pray for you: for him will I accept: lest I deal with you after your folly, in that ye have not spoken of me the thing which is right, like my servant Job. Job 42:8