The original meaning of the word lust is “strong desire” and not necessarily a sinful desire, since there are certain desires of our physical nature—such as hunger and thirst—which we have in common with the animal world and which, in themselves, are natural and not sinful. It is only their abuse that is evil. Hunger is natural lust. Gluttony is a sinful lust. Thirst is a natural lust. Intemperance is a sinful lust.