| deadly sin n. One of the seven sins—anger, covetousness, envy, gluttony, lust, pride, and sloth—that are supposed to be fatal to one's spiritual development and progress. |
deadly sin
any of the sins, usually numbering seven, dating back to the early history of Christian monasticism; they were grouped together as early as the 6th century by St. Gregory the Great. A sin was classified as deadly not merely because it was a serious offense morally but because "it gives rise to others, especially in the manner of a final cause" or motivation (St. Thomas Aquinas). The traditional catalog of the seven deadly sins is: (1) vainglory, or pride; (2) covetousness; (3) lust, understood as inordinate or illicit sexual desire; (4) envy; (5) gluttony, which usually included drunkenness; (6) anger; and (7) sloth. The classical discussion of the subject is in the Summa Theologica, by the 13th-century theologian St. Thomas Aquinas. The deadly sins were a popular theme in the morality plays and art of the European Middle Ages.
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