rigorists

/ˈrɪɡərɪsts/
noun
  1. People who insist on strict rules, principles, or standards, especially in matters of morality, religion, or conduct.
    • Some religious rigorists believe that their interpretation of the text is the only correct one.
    • The rigorists in the club demanded that every member follow the dress code exactly.
    • In the debate about school policies, the rigorists argued for harsher penalties for breaking rules.