It has been narrated that the Prince of Believers Ali bin Abi Talib (Peace be upon him) has said [similar to]: Whoever prays on the twenty ninth night of the month of Ramadan two rak'aat with the Opening of the Book [Sura Al-Fatiha - Holy Qur'an; 1:1-7] once and twenty times Say, "He is Allah , [who is] One [Sura Al-Ikhlaas - Holy Qur'an; 112: 1-4], he died as one who receives Mercy, and his book [of deeds] was raised to highest of high courts.
Úä ÃãíÑ ÇáãÄãäíä Úáí Èä ÃÈí ØÇáÈ Úáíå ÇáÓáÇã : ãä Õáì áíáÉ ÊÓÚ æÚÔÑíä ãä ÔåÑ ÑãÖÇä ÑßÚÊíä ÈÝÇÊÍÉ ÇáßÊÇÈ æÚÔÑíä ãÑÉ Þá åæ Çááå ÃÍÏ ¡ ãÇÊ ãä ÇáãÑÍæãíä ¡ æÑÝÚ ßÊÇÈå Ýí ÃÚáì Úáííä.
*VERY IMPORTANT PRAYER BELOW*
It has been narrated that the Holy Prophet (Peace be upon him and his progeny) has said [similar to]: Whoever prays in last night of the month of Ramadan ten rak'aat, reading in each rak'aat the Opening of the Book [Sura Al-Fatiha - Holy Qur'an; 1:1-7] once and Say, "He is Allah , [who is] One [Sura Al-Ikhlaas - Holy Qur'an; 112: 1-4] ten times, and he says in his rukuu' [bowing] and sujud [prostration] ten times: (Subhaan Allah walHamdulilaah wa la ilaha illa Allah waAllahu akbar), and he performs tashhahudd [Recition of Ashhadu an laa ilaha illa Allah] in each two rak'aat then does taslim. When finished from the ten rak'aat, he said after his completion of tasleem: (Astaghfir Allah) one thousand times, when he is finished from asking forgiveness [he] prostrated and said in his prostration Ya Hayyu Ya Qayuum, Ya Thal Jalaali WalIkraam, Ya Rahmaan AlDunya WalAkhira wa Raheemahuma Ya Arham AlRahimeen, Ya Ilaah Alawaleen walakhireen, aghfir lana thunubana, wataqabal mina salaatana wasiyaamana waqiyamana.
It has been narrated that the Holy Prophet (Peace be upon him and his progeny) then said [similar to]:
[I swear] by He who sent me rightfully as a prophet, that Jibraeel (Peace be upon him) told me from Israfeel, from his Lord the Blessed and High that [the person who prayed this] does not raise his head from prostration until [except that] Allah forgives him and accepts from him the [fasting of the] month of Ramadaan, and exceeds [overlooks] his sins, and [even] if [he] had sinned seventy sins [with] each sin greater than the sins of the servants, and He will accept [the deeds of] all of the people of the area [I think it means area] that he is in.
The rest is not translated, but the hadith goes onto to say that Jibareel

explains to the Holy Prophet (SAWS) the Allah (swt) accepts the prayers, fasts, and rising of the person who prayed and the others and that the acceptance is not just limited to those deeds performed in this Holy month, and that He will forgive their sins, accept their supplications.
For those unclear of the format of this tremendous prayer:
It is 10 rak'aat, with five sets of two rak'aat, in each rak'aat reciting Al-Fatiha once and Al-Tawheed 10 times, and in sujud and ruku' reciting the above-mentioned thikr [Subhaan Allah walHamdulilaah wa la ilaha illa Allah waAllahu akbar]. After the completion of the last prayer, one should do istighfaar one thousand times, and then go into sujud and recite the above-mentioned thikr, [Ya Hayyu Ya Qayuum, Ya Thal Jalaali WalIkraam, Ya Rahmaan AlDunya WalAkhira wa Raheemahuma Ya Arham AlRahimeen, Ya Ilaah Alawaleen walakhireen, aghfir lana thunubana, wataqabal mina salaatana wasiyaamana waqiyamana.] and then inshaAllah will gain the amazing reward mentioned in the hadith.
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