In the Name of Allah, the Most Gracious, the Most Merciful;
All the Praise is to Allah Subhanahu wa ta’ala. Peace and Blessings be upon Prophet Muhammad His Messenger.
Short Description: Lailatul-Qadar is the Most Blessed Night and indeed a great amount of value. It falls on one the odd nights of the last ten days of Ramadhan [21, 23, 25, 27, and 29]. The Night is better than a thousand months [i.e. worshiping Allah Subhanahu Wa Ta’ala in that night is better than worshiping Him a thousand months, i.e. 83 years and 4 months]. A believing person should strive to encounter the night with worship, if encountered all of the previous sins and misdeeds will be forgiven.
Lailatul-Qadar Is The Most Blessed Night.
A person who misses it has indeed missed a great amount of good. If a believing person is passionate to obey his Lord and increase the good deeds in his record, he should strive to encounter this night and to pass it in worship and obedience. If this is facilitated for him, all of his previous sins will be forgiven.
Allah Subhanahu Wa Ta’ala Says: “Ha-Mim. [These letters are one of the miracles of the Qur’an and none but Allah Alone knows their meanings].By the manifest Book (this Qur’an) that makes things clear. We sent it [this Qur’an] down on a blessed night [i.e. the Night of Al-Qadar in the month of Ramadhan]. 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’an 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.”
[Surah Ad-Dukhan 44:1-6]
In the above ayat Allah Subhanahu Wa Ta’ala described about Lailatul-Qadar.: “We sent it (this Qur’an) down on a blessed night” [Ad-Dukhan 44:3]. Ibn ‘Abbas and others said: “Allah sent down the Qur’an at one time from Al-Lawah-Mahfouz to Baitul ‘Izzah in the first heaven, then it was revealed to the Messenger of Allah (sallallāhu 'alayhi wa sallam) in stages according to events over twenty-three years.”
[Tafsir Ibn Kathir, 4/529]
The Night Is Better Than A Thousand Months
Allah Subhanahu Wa Ta’ala mentions its honour and great value:
“Verily, we have sent it [this Qur’an] down in the Night of Al-Qadar [Decree].And what will make you know what the Night of Al-Qadar [Decree] is?. The Night of Al-Qadar [Decree] is better than a thousand months [i.e. worshiping Allah in that night is better than worshiping Him a thousand months, i.e. 83 years and 4 months]. Therein descend the angels and the Ruh [Jibril] by Allah’s Permission with all Decrees; [All that night] there is peace [and goodness from Allah to His believing slaves] until the appearance of dawn.”
When is the Night?
The Messenger of Allāh (sallallāhu 'alayhi wa sallam) said:
"Seek it on the odd nights of the last ten days of Ramadhan." [Bukhari]
It is suggested to make a long and extensive Qiyamulail during the nights on which Lailatul-Qadar could fall [ i.e on 21, 23, 25, 27, and 29 of Ramadhan].
Solāt Tarawīh with the imam until he concludes it
Abu Dharr (radiallahu ‘anhu) relates: “We fast with Allah’s Messenger (sallallāhu 'alayhi wa sallam) in Ramadhan. He did not lead us (in qiyam) at all until the last seven (nights of Ramadhan). Then he stood with us (that night – in prayer [tarawīh]) until one third of the night had passed. He did not pray with us on the sixth. On the fifth night, he prayed with us until half of the night passed. So we said, ‘O Allah’s Messenger! Wouldn’t you pray with us the whole night?’ The Prophet (sallallāhu 'alayhi wa sallam) replied: ‘Whoever stands in prayer with the imam until he (the imam) concludes the prayer, it is recorded for him that he prayed the whole night.’…”
[Recorded by Ibn Abi Shaibah, Abu Dawud, At-Tirmidzi (who authenticated it), An-Nasa'i, Ibn Majah, at-Tahawi (in Sharh Ma’an il-Athar, Ibn Nasr, Al-Faraibi, and Al-Baihaqi. Their isnad is sahih.]
Abu Dawud said: "I heard Ahmad being asked, 'Do you like for a man to pray with the people or by himself during Ramadhan?' He replied, 'Pray with the people' I also heard him say, 'I would prefer for one to pray (qiyam) with the imam and to pray witir with him as well, for the Prophet (sallallāhu 'alayhi wa sallam) said: "When a man prays with the imam until he concludes, it is recorded that he prayed the rest of that night." [Masa'il]
Abu Hurairah (radiallahu ‘anhu) narrated that the Messenger (sallallāhu 'alayhi wa sallam) said: “Whoever stands (in qiyam) in Lailatul-Qadar [and it is facilitated for him] out of faith and expectation (of Allah’s reward), will have all of his previous sins forgiven.”
[Al-Bukhari and Muslim; the addition "and it is facilitated for him" is recorded by Ahmad from the report of ‘Ubadah Ibn As-Samit; it means that he is permitted to be among the sincere worshippers during that blessed night]
It is also suggested to make extensive supplication on this night. ‘Aishah (radiallahu ‘anha) reported that she asked Allah’s Messenger (sallallāhu 'alayhi wa sallam), “O Messenger of Allah! If I knew which night is Lailatul-Qadar, what should I say during it?” And he instructed her to say: “Allahummainna Ka’afuw Wun Tuhibbul ‘Afwa Fa’fu’ Anna” (O Allah! You are Forgiving, and you love forgiveness. So forgive us) [Recorded by Ahmad, Ibn Majah, and At-Tirmidzi; Verified to be authentic by Al-Albani]
Abandoning Worldly Pleasures for the Sake of Worship
It is further recommended to spend more time in worship during the nights on which Lailatul-Qadar is likely to be. This calls for abandoning many worldly pleasures in order to secure the time and thoughts solely for worshipping Allah Subhanahu Wa Ta’ala.
‘Aishah (radiallahu ‘anha) reported: “When the (last) ten started, the Prophet (sallallāhu 'alayhi wa sallam) would tighten his izar (i.e. he stayed away from his wives in order to have more time for worship), spend the whole night awake (in prayer), and wake up his family.”
[Al-Bukhari and Muslim]
And she also said: “Allah’s Messenger (sallallāhu 'alayhi wa sallam) used to exert more (in worship) on the last ten than on other nights.”
The Prophet (sallallāhu 'alayhi wa sallam) said: “Seek it in the last ten nights, on the odd-numbered nights.”
[Al-Bukhari and Muslim]
Ibn ‘Abbas(radiallahu ‘anhu), narrated that the Prophet (sallallāhu 'alayhi wa sallam) said: “Seek it in the last ten days of Ramadhan, when there are nine days left, and seven days left, and five days left.”
[Adapted from: The Compilation of Muhammad Al -Jibali, Islam.Com, Reference To "The Night Prayers: Qiyam and Tarawih by Muhammad Nasiruddin Al-Albani (And Other Scholars)" Via Islamhouse]