“Know, dear son, that days are but hours, and hours are but breaths, and every soul is a container, hence let not any breath pass without benefit, such that on the Day of Judgement you find an empty container and feel regret!
Be aware of every hour and how it passes, and only spend it in the best possible way;
do not neglect yourself, but render it accustomed to the noblest and best of actions,
and send to your grave that which will please you when you arrive to it.”
(Ibn al-Jawzī in his Lafat al-Kabid fī Naṣīḥat al-Walad)