What is the origin of the seven capital sins?
As commonly listed today, the seven deadly or capital sins are
They are inclinations that unchecked give rise to many sins. They are called capital sins because they are the fountainheads from which other sins flow. According to Henry Fairlie in The Seven Deadly Sins, classifying the deadly sins had its origin in the monastic movement and “the list was ﬁrst framed in the cloisters of Eastern Europe.” John Cassian of Marseilles (360-435) introduced the rules of Eastern monasticism to the West, including the notion of eight deadly sins. These sins were not identical with the list used today. Cassian’s list of sins was modified by Pope Gregory the Great in the sixth century. It is his list that we use today.
Gregory deﬁned the deadly sins in such a way that they can be applied to the ordinary conditions of life rather than seen just as temptations that must be resisted by those in monasteries. Fairlie notes it was once required in England that pastors preach on the deadly sins four times a year. That may explain why we ﬁnd the parson in Chaucer’s Canterbury Tales (“The Parson’s Tale”) preaching to the pilgrims on the seven deadly sins, inviting them to consider the extravagance of their clothing, the richness of their food, the raising of their children, greediness of landlords, deceit of merchants and the backbiting of gossips.