All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
Allah Almighty, the One, and Creator of all times and all places, gives priority to some places over some other places and some periods over some other periods.
Allah Says (what means): {And your Lord creates what He wills and chooses; not for them was the choice. Exalted is Allah and high above what they associate with Him..} [Quran 28: 68] Allah gives preference of some nights over other nights and of some days over other days.
Laylatul-Qadar is among the virtuous nights and it is the most virtuous of all nights. Allah Says about this night (what means): {The night of Al-Qadr (Decree) is better than a thousand months (i.e. worshipping Allah in that night is better than worshipping Him a thousand months, i.e. 83 years and 4 months).} [Quran 97: 3]
The act of a person in this night is better than a thousand months. This night exists in the last ten days of the month of Ramadan. The Prophet said: “Search for it in the last ten days of the month of the Ramadan.” [Al-Bukhari and Muslim]
The nights of the month of Ramadan are among the virtuous nights in general and the nights of the last ten days in particular since the reward of the acts is multiplied in this month. The Prophet used to tighten his waist belt (i.e. work hard) and used to pray all the night, and used to keep his family awake for the prayers.
The night of fifteenth of Sh'abaan is also among the virtuous nights. The Prophet said: “Allah looks upon His creatures in the night of the fifteenth of Sh'abaan and then forgives them except a polytheist or the one who keeps enmity.” However, there is no true evidence that proves celebrating or doing any special worship in this night.
In general all the nights of a Muslim are excellent nights since Allah descends every night in the last third of the night and Says: Is there anyone to invoke Me that I may respond to his invocation? Is there anyone to ask Me so that I may grant him his request? Is there anyone asking My forgiveness, so that I may forgive him?”
There are many virtuous days such as the days of the month of the Ramadan, the first ten days of the month of Dhul-Hijjah, especially the day of ‘Arafah and the day of the tenth Muharram. Monday, Thursday, and the white days (i.e. the thirteenth, fourteenth and fifteenth of every month). Fasting during the four sacred months (i.e. Dhul-Qi’dah, Dhul-Hijjah, Muharram and Rajab) is desirable. Fasting the day of ‘Arafah is desirable for the one who is not performing Hajj. The first ten days of Dhul-Hijjah are more virtuous than other days. The Prophet said: “There are absolutely no good deeds done on other days that are superior to those done on these (i.e. first ten days of Dhul-Hijjah)”. Then some companions of the Prophet said: “Not even Jihad?” He replied, “Not even Jihad, except that of a man who goes o sake for the Cause of Allah by putting himself and his property in danger (for Allah's sake) and does not return with any of those things.”
The last ten nights of the month of the Ramadan are more sacred than the first ten nights of the month of the Dhul-Hijjah and the first ten days of the month of Dhul-Hijjah are more sacred than the last ten days of the month of Ramadan. This is the preponderant opinion of the Muslim scholars. The Day of ‘Arafah is the best day in general. The Prophet said: “No day is most virtuous to Allah than the day of ‘Arafah.”
The mentioned days and all the times of a Muslim are good and appropriate for worshipping Allah. But Allah gives preference to some times over some others only to make them an opportunity for doing good deeds as much as possible and these deeds are useful for the Muslim in this life and in the Hereafter life.
Celebrating the mentioned days means using them for doing good deeds as much as possible. One should use them for fasting, praying, supplicating Allah, avoiding all kinds of innovations practiced by many people who spend these times in amusement and other useless activities.
We do not know the day of “Bara” and there is no such night in the Sharee’ah to our knowledge. And there is no true evidence specifying the night of Isra and Miraaj. All the narrations concerning these nights are weak even if it is assumed to be true, celebrating or making certain kinds of worship is forbidden since the companions of the Prophet who are the good examples for us did not do such things. If celebrating or doing any special worship would have been a good act, then they would have done them before us. Dear brother, try to follow the Sunnah only and avoid all innovations.
There are kinds of Salah called Salat al-Ragaib, which are prayed in the beginning of the month or Rajab. This is an innovation and it is not reported from the Prophet and his companions.
A Muslim should keep himself away from all innovations. All matters of worshipping Allah are reported from Allah and His Prophet and they are protected from any addition, alteration, falsification, and diminution.
Meanwhile the matters of customs are not so; those customs which do not contradict the Sharee’ah could be practiced. But anything that contradicts the Sharee’ah must be avoided.
Allah knows best.