“The lazy should be instructed that, often, if we do not do what we can when we have the opportunity, soon we will not have the opportunity to do what we want. For the desire of the mind, when it is not accompanied by the appropriate zeal, loses its desire for good works, as it is overcome by a powerful, but hidden, sloth. As it is aptly said through Solomon: ‘Sloth casts a deep sleep.’ For a lazy person perceives himself to be awake, but he grows all the more torpid from doing nothing. Thus, sloth is said to ‘cast a deep sleep’ because gradually even the vigilance of consciousness is lost when one ceases to pursue good works with zeal. And so it was well added: ‘And an idle soul will be hungry.’ For when the soul does not incline itself to greater things, neglecting itself, its desire increases for inferior things.” (Gregory the Great, The Book of Pastoral Rule, p. 125-6).