What Is Lailatul Qadar?

Lailatul Qadar (Arabic: لیلة القدر), the Night of Power, Night of Value, the Night of Decree or Night of Measures, is the anniversary of two very important dates in Islam that occurred in the month of Ramadan.

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 morn!

Summary:

This Sura describes Lailatul Qadar, the “Night of Power” in Ramadhan on which Muslims believe the Qur’an was first revealed. The “Spirit” mentioned in verse 4 is commonly interpreted as referring to the angel Jibreel (Gabriel).

The “peace” referred to is “security in which Shaytan (Iblis) cannot do any evil or any harm”, while Ibn Kathir quotes Ash-Sha’bi as saying that it refers to the angels greeting the people in the mosques throughout the night.

Lailatul Qadar occurs during an odd-numbered night within the last ten days of Ramadan, but its exact date is uncertain; due to the promises made in the Sura and in various hadith. Muslims consider it a particularly good time for prayer, supplication, and repentance to God.