Felix culpa is a Latin phrase that comes from the words Felix (meaning "happy," "lucky," or "blessed") and Culpa (meaning "fault" or "fall"), and in the Catholic tradition is most often translated "happy fault."
The Latin expression felix culpa derives from St. Augustine’s famous allusion to one unfortunate event, the Fall of Man, Adam and Eve's fall and the loss of the Garden of Eden, known theologically as the source of original sin. The phrase is sung annually in the Exsultet of the Easter Vigil: "O felix culpa quae talem et tantum meruit habere redemptorem," "O happy fault that merited such and so great a Redeemer." The medieval theologian Thomas Aquinas[1] cited this line when he explained how the principle that "God allows evils to happen in order to bring a greater good therefrom" underlies the causal relation between original sin and the Divine Redeemer's Incarnation, thus concluding that a higher state is not inhibited by sin. The Catholic saint Ambrose also speaks of the fortunate ruin of Adam in the Garden of Eden in that his sin brought more good to humanity than if he had stayed perfectly innocent.[2]
The concept also comes up in Hebrew tradition in the Exodus of the Israelites from Egypt and is associated with God’s judgment. Although it is not a fall, the thinking goes that without their exile in the desert the Israelites would not have the joy of finding their promised land. With their suffering came the hope of victory and their life restored.[2]
In a literary context, the term "felix culpa" can describe how a series of miserable events will eventually lead to a happier outcome. The theological concept is one of the underlying themes of Raphael Carter's science fiction novel The Fortunate Fall; the novel's title derives explicitly from the Latin phrase. It is also the theme of the fifteenth-century English text Adam lay ybounden, of unknown authorship, and it is used in various guises, such as "Foenix culprit" and "phaymix cupplerts" by James Joyce in Finnegans Wake.