Abû Hurayra radiyallahu `anhu relates that the Holy Prophet sallallahu `alayhi wa sallam said:
"Whosoever worshipped on Laylatul-Qadr, with faith and with a sincere intention, all of his previous sins are forgiven." (from al-Bukhârî and Muslim)
From the nights of the blessed month of Ramadan, one is known as Laylatul-Qadr and during it, blessings, rewards and an abundance of good can be gained.
Allah Most high has made worship during this night worth than a thousand months, i.e. anyone who spent this night in worship, would have worshipped an equivalent of eighty three years and four months - khayru(n)m-minalfi shahr