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mortal sin

noun

Definition of mortal sin

:a sin (such as murder) that is deliberately committed and is of such serious consequence according to Thomist theology that it deprives the soul of sanctifying grace — compare venial sin 1

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First Known Use of mortal sin

15th century

MORTAL SIN Defined for English Language Learners

mortal sin

noun

Definition of mortal sin for English Language Learners

  • in the Roman Catholic Church : a sin (such as murder) that will result in punishment that lasts forever unless the person who has sinned sincerely confesses to God and asks to be forgiven

Learn More about mortal sin

  1. See words that rhyme with mortal sin Britannica.com: Encyclopedia article about mortal sin

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