The most common and most likely answer to this crossword clue is the 8 letter word MARTYRED
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The straight part
We know that "punished for beliefs" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case punished for beliefs = martyred.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does MARTYRED mean?
MARTYRED verb- To make someone into a martyr by putting him or her to death for adhering to, or acting in accordance with, some belief, especially religious; to sacrifice on account of faith or profession.
- To persecute.
- To torment; to torture.