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In the past, lust was categorized as one of the seven capital vices, i.e. one of the seven deadly sins. However, in contemporary language it seems that lust is now simply equated with sexual desire. I think that this is a mistake, and a mistake that matters. This distinction has nothing to do with religious prudery, but rather with the place of sexual desire in a fulfilled human life. Religion and sex don't have the best track record, in many ways. And yet in a recent survey religious individuals reported high levels of satisfaction regarding sex. Even the medieval philosopher and theologian Saint Thomas Aquinas believed that sexual intercourse would have been more pleasurable in the Garden of Eden before the Fall of humanity than it is now.
Setting particularly religious views aside, is there a way to distinguish between sexual desire and lust that will be helpful? The difference is that sexual desire, in its proper place and expression, is a vital and good part of our humanity. In lust, however, we fail to respect our own dignity and the dignity of our partner.
Consider the following definition of lust:
Lust...pretends sex and sexual pleasure are a party for one. Lust makes sexual pleasure all about me. It is a self-gratification project. This feature of lust more than any other puts it in opposition to well-ordered sexual enjoyment. In lust, sexual pleasure is divorced from mutual self-giving...I want my pleasure, says the lustful one, and I want it now. (Glittering Vices, p. 164)
Simply stated, lust is the excessive desire for one's own sexual pleasure. The point is not that desire for such pleasure is wrong, but rather that at its best sexual intercourse is an act of mutual self-giving and even sacrifice, rather than mere mutual masturbation. Non-lustful sexual desire includes a desire for one's own pleasure, but also a desire for the pleasure of the other. It also includes a desire for him or her as a person and not a mere body to be used for one's own purposes. Sex is not merely recreation, it is also a means of the unification of two people, in both body and spirit. In this way, sex can express and foster a meaningful unity and harmony between human beings. The desire for this type of human relationship is good and preferable to the self-centeredness of and ultimate dissatisfaction produced by mere lust.
For more on this and the other seven capital vices see Glittering Vices, from which much of the above is drawn.
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