The following answers and excerpts outline the view of experts in relation to the night of 15 Shaʿbān and the status of the fast of 15 Shaʿbān.
WHAT ARE THE VIRTUES OF THE NIGHT OF 15 SHAʿBĀN?
بسم الله الرحمن الرحیم
There are a number of Aḥādīth recorded by Imam Mundhirī (d. 656/1258) in al-Targīb Wa al-Tarhīb (3: 459) that outline the virtues of the 15th night of Shaʿbān. The Almighty Allah descends unto the seventh heaven, showers his mercy in abundance and forgives his servants. According to one narration, Almighty Allah liberates people from the fire of hell equivalent to the number of hair on the goats of Banū Kalb, an Arab tribe. However, there are certain people exempt from these virtues. They include: a polytheist, a person bearing enmity and hatred without valid reason, a murderer, a prostitute, an alcohol addict, a disobeyer of parents, a person who breaks relations, and a person whose trousers extend beneath his ankles.
Allah knows best
16 Ṣafar 1427 / 16 March 2006
UPDATE – FASTING ON 15 SHAʿBĀN
Regarding the fast of 15 Shaʿbān, one may fast on this day and will be rewarded. This is because fasting in the month of Shaʿbān is Sunnah. However, there is no specific virtue for fasting on this day and therefore its virtue is equivalent to fasting any other day in Shaʿbān. This has been mentioned by many scholars including our respected teacher Shaykh Muḥammad Yūnus Jownpūrī (b. 1355/1936 – ), Mufti Muḥammad Taqī ʿUthmānī (b. 1362/1943 – ), Mawlānā Faḍl al-Raḥmān al-Aʿẓamī (b. 1356/1946 – ), Mufti Rashīd Aḥmad Ludyānwī (d. 1422/2002) and my respected father Mufti Shabbīr Aḥmad (b. 1376 / 1957 – ). It is important to note this so that one does not think that fasting on this day is superior and more virtuous than fasting on other days in Shaʿbān.
For further details, please refer to the links and articles below.
The Fast and Virtues of 15 Shaban from Al Yawaqeet Al Ghaliyah (By Shaykhul Hadith Moulana Muhammad Yunus Jownpuri Sahib) (The relevant extract regarding the mid Shaʿban fast has been translated and published below).
Shabe Baraat – Research on 15th of Shaban from Ahsanul Fatawa (By Mufti Rashid Ahmed Ludhyanwi) (The relevant extract regarding the mid Shaʿban fast has been translated and published below).
Shabe Baraat – The 15th of Sha’ban in light of the Qur’an and Sunnah (By Moulana Fazlur Rahman ‘Azmi) (A brief extract regarding the mid Shaʿban fast has been translated and published below).
1 Rajab 1436 / 19 April 2015
THE VIEWS OF FIVE LEADING SCHOLARS REGARDING THE SOLE FAST OF 15 SHAʿBĀN
(1) The View of Mufti Rashīd Aḥmad Ludyānwī (d. 1422/2002) regarding the fast of 15 Shaʿbān
Mufti Rashīd Aḥmad Ludyānwī writes in Aḥsan al-Fatāwā (10: 80):
“The fast of this day is not established through any reliable narration. It is neither mentioned in any book of jurisprudence. Therefore, to regard it as Sunnah or Mustaḥab is impermissible.”
(2) The View of Shaykh al-Islām Mufti Muḥammad Taqī ʿUthmānī (b. 1362/1943) regarding the fast of 15 Shaʿbān
The following are extracts from two speeches of Shaykh al-Islām Mufti Muḥammad Taqī ʿUthmānī:
“One final point in relation to 15 Shaʿbān I would like to mention is regarding the fast of 15 Shaʿbān. There is one narration that mentions the virtue of the fast of 15 Shaʿbān. However, it is an extremely weak narration and the scholars of ḥadīth and jurisprudence have not acted upon it. Thus, when the jurists mention the details of the optional fasts, there is no mention of the fast of 15 Shaʿbān in the books of jurisprudence. Therefore, the correct view is that there is virtue of fasting on each day of Shaʿbān from 1st of Shaʿbān until the end of the month except the final two days. Apart from these two days, there is virtue of fasting on any day. Accordingly, there is virtue for this day 15 Shaʿbān as well. Also, in particular, the Prophet ﷺ would frequently fast during Ayyām Bīḍ: 13, 14 and 15 of each month. Therefore, if someone fasts on 15 Shaʿbān because of this, this is fine. However, there is no virtue to fast on 15 Shaʿbān because of it being 15 Shaʿbān.”
“There is no sound narration regarding the specific fast of 15 Shaʿbān.”
“It is not appropriate to fast specifically on 15 Shaʿbān if the intention is that it holds additional virtue.”
(3) The View of Mawlānā Faḍl al-Raḥmān al-Aʿẓamī (b. 1356/1946 – ) regarding the fast of 15 Shaʿbān
The leading ḥadīth expert Mawlānā Faḍl al-Raḥmān writes in his book Shab Barāt Kī Ḥaqīqat (p. 23):
“Fasting on the 15th of Shaʿbān is not established from ḥadīth. Some people are of the misconception that fasting on the 15th of Shaʿbān is Sunnah. They have been deceived by the ḥadīth of Ḥaḍrat ʿAlī (may Allah be pleased with him) that appears in Ibn Mājah. This narration is totally unreliable.”
(4) The View of Shaykh al-Hadith Mufti Shabbīr Aḥmad (b. 1376 / 1957 – )
I asked my respected father Shaykh al-Ḥadīth Mufti Shabbīr Aḥmad regarding the prevalent fast of 15 Shaʿban. He replied that singling out the fast of 15 of Shaʿban is not established from the Aḥādīth. In the time of the Prophet ﷺ, the month of Shaʿbān came every year. We do not find in the books of ḥadīth that the companions regarded fasting on this day as holding some special significance or virtue. We do not find that they fasted on this day specifically in the way that they fasted on other days of the year wherein fasting is Sunnah. If fasting on this day held some special significance and virtue, this would have been affirmed via authentic narrations. Similarly, we do not find this practice of fasting specifically on 15 Shaʿbān in the time of the tābiʿūn or the tabaʿ tābiʿīn. The scholars of jurisprudence from the time of the Salaf have not mentioned this fast. It was only in a later era that fasting on this day was emphasised and this did not occur except in certain parts of the Muslim world. Since then, the practice has continued in these areas. It is worth noting that fasting generally in the month of Shaʿbān is highly recommended and is a Sunnah. The Prophet ﷺ would regularly fast in this month. Accordingly, one may fast on 15 Shaʿbān but should not regard it as more virtuous than fasting on other days in the blessed month.
(5) Extract from the detailed research of Muḥaddith al-ʿAṣr Shaykh al-Ḥadīth Mawlānā Muḥammad Yūnus Jownpūrī (b. 1355/1936 – )
Our respected teacher Muḥaddith al-ʿAṣr Shaykh al-Ḥadīth Mawlānā Muḥammad Yūnus Jownpūrī writes in al-Yawāqīt al-Ghāliyah (2: 306):
“The Ruling on the fast of 15 Shaʿbān
The fifth section is whether the fast of 15 Shaʿbān is an innovation. According to my knowledge, the earlier jurists have not mentioned this fast. There is no mention of this fast in the reliable Mutūn (classical texts), nor in the available books of Imām Muḥammad ibn al-Ḥasan: Kitāb al-Aṣl, Jāmiʿ Ṣaghīr, Kitāb al-ʾĀthār, Kitāb al-Ḥujaj and Kitāb al-Siyar al-Kabīr. The later scholars have also not mentioned this fast.
However, the general fast of Shaʿbān has been regarded as desirable. It is stated in Fatāwā ʿĀlamgīriyyah (1: 103): “The desired fasts are various: first the fast of Muḥarram, second the fast of Rajab, third the fast of Shaʿbān. The fast of ʿĀshūrāʾ is on 10 Muḥarram according to the general scholars and companions. This has been mentioned in al-Ẓahīriyyah.” The evidence for the desirability of the general fast of Shaʿbān are those narrations that mention the extent to which the Prophet ﷺ would fast in this month, either the full month or most of the month, as has been mentioned above.
Shaykh ʿAbd al-Ḥaq Muḥaddith Dehlawī has mentioned the desirability of the general fast of Shaʿbān in Sharḥ Sifr al-Saʿādah (p. 310). He has not mentioned the fast of mid Shaʿbān at all. In Ashiʿah al-Lamaʿāt (1: 549) he has sufficed with the translation of the aforementioned narration of Ibn Mājah. Similarly, in Mā Thabata Bi al-Sunnah (p. 199) he has sufficed with the mention of the narration of Ibn Mājah. The status of the narration of Ibn Mājah has been mentioned above.
Similarly, this fast has not been mentioned in the available Ḥanbalī books such as Mukhtaṣar al-Khiraqī and its commentary al-Mughnī, or al-Muqniʿ and its commentary al-Shāfī.
Similarly, there is no mention of this fast in the famous Shāfiʿī books such as Kitāb al-Umm of Imām Shāfiʿī, al-Muhadhdhab of Shīrāzī, Sharḥ al-Muhadhdhab of Nawawī, al-Minhāj, al-Manhaj and Tuḥfah al-Muḥtāj. However, ʿAbd al-Ḥamīd al-Shirwānī has indicated it is Mandūb (desirable) in the commentary of Tuḥfah al-Muḥtāj.
Similarly, there is no mention of this fast in the Mālikī books such as Mukhtaṣar al-Khalīl and its commentary Jawāhir al-Iklīl, or in Risālah Ibn Abī Zayd and its commentary Kifāyah al-Ṭālib, and neither in the commentary of Kifāyah by ʿAllāmah ʿAlī Ṣaʿīdī al-ʿAdawī.
For this reason, as the fast of 15 Shaʿbān does not have sufficient basis from a ḥadīth perspective, the statements of jurists do not provide any basis either. Most probably the jurists have remained silent because they disregarded the narration.
As far as some later Shāfiʿī scholars who have mentioned it is Mandūb or indicated towards that, it appears that they did not look at the chain of the narration, or if they did, they did not fully research it.
If the [fast of] 15 Shaʿbān is put aside, the general fast of Shaʿbān is established through ṣaḥīḥ (sound) and ḥasan (agreeable) narrations that have been outlined towards the end of the answer in section one of the answer. These narrations indicate that fasting in Shaʿbān without specifying [any particular day] is desirable, following the Prophet ﷺ. This is what the author of al-Ẓahīriyyah and other Ḥanafī jurists intended when they mentioned Shaʿbān from amongst the desirable fasts. Otherwise, they would have explicitly mentioned the fast of 15 Shaʿbān if that was intended.
Thus, the correct view now appears to be that specifying the fast of 15 Shaʿbān and solely fasting on that day is a Bidʿah (innovation) unless it is accompanied with the fast of 13 and 14, so that they become the fast of Ayyām Bīḍ.
After writing thus far, I found a passage in Fayḍ al-Qadīr (2: 317) of ʿAllāmah Munāwī which holds the status of Matn (principle text) for the aforementioned research: “Majd ibn Taymiyah said: There are sound narrations for the virtues of the fast of Shaʿbān. As regards the sole fast of mid Shaʿbān, there is no basis for this. In fact, it is detestable. He further said: Similarly, it is detestable to make it a festival in which food and sweets are cooked and adornments are made visible. This is from the innovated invented festivals that have no basis”. ʿAllāmah Munāwī has remained silent after citing this passage. It can therefore be deduced that he is in agreement with ʿAllāmah Majd al-Dīn ibn Taymiyah.”
Translation and footnotes by Yusuf Shabbir
1 Rajab 1437 / 8 April 2016
 Many scholars including Imām Nawawī (d. 676/1277), Shaykh al-Islām Ibn Taymiyah (d. 728/1328) and Ḥāfiḍ Ibn Ḥajar al-ʿAsqalānī (d. 852/1449) have affirmed that there is no specific virtue of fasting in the month of Rajab (Sharḥ Muslim, 8: 39; Majmūʿ al-Fatawā, 25: 290; Mawāhib al-Jalīl, 2: 408; Fayḍ al-Qadīr, 4: 18; Nayl al-Awṭār, 4: 293). There are however narrations that suggest that it is desirable to fast in the sacred months; this includes Rajab.
 Refer to the original source that includes the detailed research.
 ʿAllāmah ʿAbd al-Raʾūf al-Munāwī (d. 1031/1622) is a great Shāfiʿī scholar and saint who authored more than 100 books (Khulāṣah al-Athar, 2: 193; al-Badr al-Ṭāliʿ, 1: 357; al-Aʿlām, 6: 204).
 ʿAllāmah Abū al-Barakāt Majd al-Din ibn Taymiyah (d. 652/1254) is a Ḥanbalī scholar famously known as the jurist of his era and the Shaykh of the Ḥanābilah. He is the grandfather of the famous Shaykh al-Islām Ibn Taymiyah (Siyar ʿAlām al-Nubalāʾ, 23: 291; Dhayl Ṭabaqāt al-Ḥanābilah, 4: 1).