The great tābi‘ī, Hasan al-Basri rahimahullāh once said:

O son of Ādam! You are but (a collection of) days: when a day goes, a part of you goes.

A day that has passed will never return. Every morning at sunrise the day says:

Whoever is able to do some good should do it, for I will never return to you.

Just think! Our childhood days have passed; for many their youth has passed; others have reached old age and are waiting only for death to come. Allāh ta‘ālā says:

…Indeed, when the term appointed by Allāh comes, it cannot be delayed… (71:4) Read more