His highness Muhammad (s.a.w) says:
If the holy month of Ramadan passes by someone and s/he’s not forgiven, s/he’s the wretched and most evil person on earth.

Why?

This month is the month when your breath… every breath, is recorded as [saying] a Subhan Allah for you in the Book of your deeds.

This month is the month that, if you sleep, your sleep is recorded as worship.
 
This month is the month when the [reward of] an obligatory act you do is recorded 70 times more than other times.

 In this month, you read one verse of the Quran (God will record [its reward] as reading the whole Quran for you),

And with all the goodness that the holy month of Ramadan has, if it passes and we are not forgiven, his highness Muhammad (s.w.a.) says:

This person is the wretched and most evil person on earth.