Laylat al-Qadr لیلة القدر‎

We have indeed revealed this (Message) in the Night of Power:
And what will explain to thee what the night of power is?
The Night of Power is better than a thousand months.
Therein come down the angels and the Spirit by Allah's permission, on every errand:
Peace!...This until the rise of dawn!
—Sura 97 (Al-Qadr), āyāt 1-5

Read more about Laylut al-Qadr here.

Ramadan Blessings

The exact day that Laylat al-Qadr (لیلة القدر‎) occurs has, by tradition, been a matter of discussion. The Qur'an says that this night is better than a thousand months and that on this night the angels descend to earth. There are various Hadith pointing to different days during the last 10 days of Ramadan. Many Sunni Muslims believe that the Night of Excellence is the 27th of Ramadan. 
 

Allah's Apostle said, "When the month of Ramadan starts, the gates of the heaven are opened and the gates of Hell are closed and the devils are chained." [Bukhari] ...

"Whoever establishes the prayers on the night of Qadr out of sincere faith and hoping to attain Allah's rewards (not to show off) then all his past sins will be forgiven." [Bukhari] ...