moral beliefs that are strict, critical, and severe in dictating one's conduct and religion, especially involving indulgences and sex;
e.g. He followed a system of moral puritanism, denying himself of many comforts.
(noun)
the principles and practices that are characteristic of a group of English Protestants in the 16th and 17th centuries (the Puritans) who aimed to simplify their modes of worship;
e.g. He is one of the major scholars of Puritanism and describes the system's major beliefs in this text.