Seven deadly sins who identified seven or eight evil thoughts or spirits that one needed to overcome. Evagrius' pupil John Cassian, with his book "The Institutes," brought the classification to Europe, where it became fundamental to Catholic confessional practices as evident in penitential manuals, sermons like "The Parson's Tale" from Chaucer's "Canterbury Tales," and artworks like Dante's "Purgatory" (where the penitents of Mount Purgatory are depicted as being grouped and penanced according to the worst capital sin they committed). The Catholic Church used the concept of the deadly sins in order to help people curb their inclination towards evil before dire consequences and
Seven deadly sins of all sins, it has been deemed the devil's most prominent trait. C.S. Lewis writes, in "Mere Christianity", that pride is the "anti-God" state, the position in which the ego and the self are directly opposed to God: "Unchastity, anger, greed, drunkenness, and all that, are mere fleabites in comparison: it was through Pride that the devil became the devil: Pride leads to every other vice: it is the complete anti-God state of mind." Pride is understood to sever the spirit from God, as well as His life-and-grace-giving Presence. One can be prideful for different reasons. Author Ichabod Spencer states