- al Ghazali from The Alchemy of Happiness

He, therefore is a wise man who, after his morning prayers, spends a whole hour in making spiritual reckoning and says to his soul, 

"Oh my soul, thou hast only one life: no single moment that has passed can be recovered, for in the counsel of Allah the number of breaths allotted thee is fixed, and cannot be increased. When life is over no further spiritual traffic is possible for thee; therefore what thou dost do now; treat this day as if thy life had been already spent, and this were an extra day granted thee by the special favour of the Almighty. What can be greater folly than to lose it ?"