An excessive preoccupation with or obsession about the Ten Commandments or moral laws.
From decalog/decalogue + -mania (excessive preoccupation). The -mania suffix comes from Greek 'mania' meaning madness or excessive enthusiasm.
A decalomania would describe someone obsessively focused on moral perfection and strict adherence to commandments—some religious reformers throughout history could be described as decalomaniacs!
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