Lust (Luxuria)

Lust, luxuria, is defined in the tradition as desire for sexual pleasure sought outside its proper order rather than as sexual desire itself, and both Aquinas and the Catechism of the Catholic Church are explicit that the appetite is natural and that the disorder lies in its separation from its ends. In Evagrius and Cassian the corresponding logismos is porneia, and the monastic treatment is concerned with the management of thought and imagination rather than with acts. Aquinas subdivides the vice into species and treats it, with gluttony, as one of the two vices of the flesh, which he holds to be less grave than the spiritual vices of pride and envy though often more shameful, a distinction that runs against the popular assumption that the sexual sins are the worst.

The Eastern Christian tradition never systematized the vice into the same confessional casuistry as the Latin West; instead, the eighteenth-century Philokalia, an anthology of ascetic texts compiled by Nikodemos of the Holy Mountain and Makarios of Corinth that remains central to Orthodox spiritual practice, preserves Evagrius's and Cassian's original desert vocabulary of porneia largely unchanged, treating it as a thought to be watched and refused rather than an act to be classified into species and degrees the way Western manuals of moral theology, built for use in the confessional, came to require.

The history of Christian teaching on this vice is one where a historical account has to record the harm as well as the doctrine. Ascetic suspicion of the body, the identification of women with temptation in a great deal of patristic and medieval writing, the treatment of sexual sin as uniquely defining, and the disciplinary regimes built on all three, have caused documented damage, and this is acknowledged within the churches as well as outside them. At the same time the tradition's own logic, that the disorder is in the will rather than in the body, and Aquinas's ranking of the spiritual vices above the carnal, has always been available as a counterweight and has been drawn on in modern reappraisals. The atlas records the doctrine as the tradition states it; a reader is entitled to both the statement and the record of its effects.

Augustine's own theological formulation of concupiscence in the Confessions, shaped explicitly by his account of his own pre-conversion sexual life, became the template much later medieval penitential literature built on; the early medieval penitentials, manuals assigning specific tariffs of penance for particular sins, devoted disproportionate attention to sexual transgression compared with other categories of wrongdoing, a documented imbalance historians of medieval religion cite as evidence of how far pastoral practice outran the more measured theological position Aquinas would later articulate. Modern Catholic moral theologians, Margaret Farley among them, have argued for reconstructing sexual ethics around relational justice rather than the older act-centered casuistry, a reappraisal that remains contested within the church rather than settled.