Uncontrolled sexual passions
Inordinate desire for sexual pleasure
Idolatry of the flesh
Slavery of the passions
Lust is using sexuality for the purposes of self enhancement and self satisfaction. Lust is not simply sexuality nor sexual drives; it is the perversion of these necessary and creative aspects of humanness. Lust is self destructive in the sense that it denies the ability to make choices about partners, it takes whoever is available. It denies the need and ability to give and receive. It only takes. Lust is destructive of the other. Its end is neither procreation nor an expression of love. Lust does not desire continuity of relationship but immediate gratification. At its root is pride and covetousness, pride in the desire to control and covetousness in the need to possess. Lust in its expression is cruel, at the least in the sense of being exploitative and a betrayal of the deepest levels of trust. It sometimes evokes passion in others only to reject them. At its worst sexual lust is rape. Lust is destructive of society. It refuses to accept responsibility for gratification of desires, sexual acts nor overwhelming desires, such as, the lust for power.
In order, therefore, to restore due order in this matter of marriage, it is necessary that all should bear in mind what is the divine plan and strive to conform to it. Wherefore, since the chief obstacle to this study is the power of unbridled lust, which indeed is the most potent cause of sinning against the sacred laws of matrimony, and since man cannot hold in check his passions, unless he first subject himself to God, this must be his primary endeavor, in accordance with the plan divinely ordained. (Papal Encyclical, Casti Connubii, 31 December 1930).