it is clear that the desires weary and fatigue the soul; for they are like restless and discontented children, who are ever demanding this or that from their mother, and are never contented. And even as one that digs because he covets a treasure is wearied and fatigued, even so is the soul wearied and fatigued in order to attain that which its desires demand of it; and although in the end it may attain it, it is still weary, because it is never satisfied

(Saint John of the Cross)