Shaikhul Islam was asked while he was in prison of Qal’ah, year 706 AH: When is lailatul Qadr?
He replied (abbreviated):
Lailatul Qadr falls in the last ten nights of Ramadan. In the odd nights.
However, the odd nights could be determined by looking at the previous days, so it should be sought on the 21st, 23rd, 25th, 27th and 29th …
Or it could be determined by looking at what is remaining. The Prophet (saw) said: “Seek it at the remaining 9, 7, 5, 3 night.” Based on this Lailatulqadr could fall on the even nights of the last ten nights. This is how Abu Sa’eed Al-Khudri (ra) understood the Hadeeth.
Therefore, a believer is to seek Lailatul Qadr in all of the last ten nights. More so in the last 7 nights. And even more so on the 27th as Ubai bin Ka’b (ra) used to swear on this.
Month Of The Quran 