'Day' in the Bible

A good name [is] better than precious ointment, and the day of death [is better] than the day of one's birth.

In the day of prosperity, rejoice! But in the day of adversity, consider! For God made one in place of another so that mortals cannot find out what will happen {in the future}.

Just as no one can control the wind to restrain the wind, so also no one can control the day of his death. Just as no one is discharged in time of war, so wickedness will not deliver the wicked.

I applied my mind to know wisdom and to understand the business that is done on earth--how neither day nor night one's eyes see sleep.