SHAFAQNA – Zayd ibn Harithah was not feeling well and was seating and leaning to one of the pillars of the Mosque. The Prophet of Islam (PBUH) asked Zayd: How did you wake up this morning? Zayd replied: In the state of certainty. The Prophet (PBUH) said: Everything has a sign, what is the sign of your certainty? Zayd replied: The sign of my certainty is that, I cannot sleep at night, I hear the roar of the hellfire and see the blessings of the paradise.
Now, you consider our situations, the moment our head touch the pillow, if the world goes under water, our sleep will not be effected. And in the morning, some can hardly wake up to perform the Fajr Salaat (morning prayer). This is because we lack believe and certainty .
 Ethical guidance by Ayatollah Mojtahedi Tehrani, Darul Ershaad Website, 09/06/2015.