Allaah forgives the previous sins of the one who stays up and prays during this night out of faith and in hope of earning the reward from Him.
Muslims all over the world fast in the Holy of Ramadan. The real purpose of fasting is spiritual cleansing and becoming a good human being. It is a month dedicated to burning sins.
The Prophet (peace and blessings of Allaah be upon him) used to strive hard (in worship) during the last ten days of Ramadaan in a way that he did not strive at any other times.
In al-Saheehayn it is reported from the hadeeth of ‘Aa’ishah (may Allaah be pleased with her) that when the last ten days of Ramadaan came, the Prophet (peace and blessings of Allaah be upon him) would stay up at night, wake his family and gird his loins. (al-Bukhaari, 1920; Muslim, 1174).
The phrase “stay up at night” means that he would stay awake, spending the night in prayer, etc. It was reported in another hadeeth that ‘Aa’ishah (may Allaah be pleased with her) said: “I never saw the Prophet (peace and blessings of Allaah be upon him) recite the entire Qur’aan in one night, or spend a whole night in prayer until the morning, or fast an entire month, except in Ramadaan.”
The Muslim should follow the example of the Prophet (peace and blessings of Allaah be upon him), for he is the best example, and he should strive hard in worshipping Allaah. He should not waste the hours of these days and nights. For we do not know, perhaps this time will never come again, for the spoiler of pleasures, i.e., death, which must come to all men, may come and snatch him and his life will end; then he will feel regret at the time when regret will be of no avail.
Among the unique virtues of these special nights is that Laylat al-Qadr is among them. Allaah says (interpretation of the meaning):
“Haa-Meem. [These letters are one of the miracles of the Qur’aan and none but Allaah (Alone) knows their meanings.]
By the manifest Book (this Qur’aan) that makes things clear.
We sent it (this Qur’aan) down on a blessed night [(i.e. the Night of Al-Qadr) in the month of Ramadaan]. Verily, We are ever warning [mankind that Our Torment will reach those who disbelieve in Our Oneness of Lordship and in Our Oneness of worship].
Therein (that night) is decreed every matter of ordainments.
As a Command (or this Qur’aan or the Decree of every matter) from Us. Verily, We are ever sending (the Messengers),
(As) a mercy from your Lord. Verily, He is the All-Hearer, the All-Knower.” [al-Dukhaan 44:1-6]
Allaah forgives the previous sins of the one who stays up and prays during this night out of faith and in hope of earning the reward from Him. It was reported in the hadeeth of Abu Hurayrah (may Allaah be pleased with him) that the Prophet (peace and blessings of Allaah be upon him) said: “Whoever fasts the month of Ramadaan out of faith and in the hope of earning reward, all his previous sins will be forgiven, and whoever stays up during Laylat al-Qadr out of faith and in the hope of earning reward, all his previous sins will be forgiven.” (Agreed upon).
The phrase “out of faith and in the hope of earning reward” means, believing in Allaah’s promise of reward for this, and seeking the reward, with no other aim or purpose, such as showing off etc.
The Night of Al-Qadr (Decree) is better than a thousand months means, it is better than over eighty-three years. This is a great virtue, the value of which no one can fully understand except the Lord of the Worlds, may He be blessed and exalted.
This encourages the Muslim to spend this night in prayer and to seek the Face of Allaah by doing so. The Prophet (peace and blessings of Allaah be upon him) used to seek this night, hoping to gain some good from it, and he is the example for this Ummah.
Dua for Lailat-ul-Qadr
‘A’isha said, “I said, ‘Messenger of Allah, if I know what night the Night of Power is, what do you think I should say during it?’ He said, ‘Say: “O Allah, You are Pardoning and you love pardon, so pardon me.”‘” (Tirmidhi)
اللْهُمَّ إِنَّكَ عَفُوٌّ تُحِبُّ الْعَفْوَ فَاعْفُعَنِّي
Allahumma innaka `afuwwun tuhibbul `afwa fa`fu `annee
We ask Allaah to accept our fasting our prayer at night, and to help us to remember Him and to thank Him and to worship Him properly. May Allaah bless our Prophet Muhammad.
Taken from Islamqa.info