Yes, there is Hadith evidence for 15th Shaban.
مُعَاذِ بْنِ جَبَلٍ، عَنِ النَّبِيِّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ قَالَ: «يَطَّلِعُ اللهُ عَزَّ وَجَلَّ عَلَى خَلْقِهِ لَيْلَةَ النِّصْفِ مِنْ شَعْبَانَ فَيَغْفِرُ لِجَمِيعِ خَلْقِهِ إِلَّا لِمُشْرِكٍ أَوْ مُشَاحِنٍ»
Mu’aadh ibn Jabal narrated from the Prophet ﷺ that he ﷺ said, ‘Allah (Most High) looks upon his creation on the night of the middle of Shaban, and forgives all of his creation except the polytheist and the hostile person.’ (Tabarani al-Mo’jam al-Kabeer, 215).
This Hadith has sound narrators according to Imam al-Haythami:
رَوَاهُ الطَّبَرَانِيُّ فِي الْكَبِيرِ وَالْأَوْسَطِ وَرِجَالُهُمَا ثِقَاتٌ.
It is narrated by (Imam) al-Tabarani in al-Kabeer and al-Awsat, and the narrators are sound. (Majma al-Zawaid).
This Hadith is also narrated in Ibn Maja (1390) with a slightly different chain of narrators (Sanad). It is weak in Ibn Maja due to a narrator called Ibn Lahi’ah. However, Shaykh Shuayb Arnawut mentioned in his footnote that the Hadith is Hasan due to other narrations. So regarding this narration not only do we have the likelihood of it being sound in Tabarani but it has other narrations strengthening it too.
The concept of Hadith narrations strengthening each other is well established in the science of Hadith.
إذا روي الحديث من وجوه ضعيفة لا يلزم أن يحصل من مجموعها حسن، بل ما كان ضعفه لضعف حفظ راويه الصدوق الأمين زال بمجيئه من وجه آخر وصار حسناً، وكذا إذا كان ضعفه بالإرسال زال بمجيئه من وجه آخر، وأما الضعف لفسق الراوي فلا يؤثر فيه موافقة غيره، والله أعلم. (التقريب والتيسير لمعرفة سنن البشير النذير في أصول الحديث)
If a Hadith is narrated with a number of weak chains, it is not necessary that it acquire the status of being Hasan due to them coming together (and strengthening each other). Rather, a Hadith that is weak due to weakness in the memory of a truthful, trustworthy narrator will have the weakness removed when it is narrated through another chain, and thus become Hasan. Likewise, if the weakness was due to being Mursal, it will be removed when it is narrated through another chain. As for the weakness (of a Hadith) due to a narrator’s immorality, the support of other narrations does not affect it, and Allah (Most High) knows best. (Imam Nawawi, al-Taqreeb).
There are many other narrations that speak about the virtue of the 15th of Shaban.
فَقَالَ: «إِنَّ اللَّهَ عَزَّ وَجَلَّ يَنْزِلُ لَيْلَةَ النِّصْفِ مِنْ شَعْبَانَ إِلَى السَّمَاءِ الدُّنْيَا، فَيَغْفِرُ لِأَكْثَرَ مِنْ عَدَدِ شَعْرِ غَنَمِ كَلْبٍ»
The Prophet ﷺ said, ‘Indeed Allah (Most High) descends to the lowest heaven on the night of the middle of Shaban and forgives more people than the wool fibers of the sheep of (the tribe of) Kalb.’ (Tirmidhi, 739).
Imam Tirmidhi commented on the weakness of this Hadith saying:
وَسَمِعْتُ مُحَمَّدًا يُضَعِّفُ هَذَا الحَدِيثَ
I heard Muhamad (Imam al-Bukhari) saying this this Hadith is weak.
The fact that this Hadith is weak is not a concern, for two reasons. Firstly, as seen above, there are other Hadith that strengthen it. Secondly weak Hadith can be used for Nafl matters such as this.
ويَجُوزُ رِوَايَةُ ما عدا الموضُوعَ في بَابِ التَّرْغِيبِ والتَّرْهِيبِ والقَصَصِ والمواعِظِ ونحوِ ذَلِكَ إلا في صِفاتِ اللهِ -عَزَّ وجَلَّ-، وفي بابِ الحَلالِ والحرَامِ. (الباعث الحثيث شرح اختصار علوم الحديث)
It is permitted to narrate anything that is not fabricated when it relates to encouraging (good deeds) and discouraging (sins), stories, reminders, and the like. However, it is not permitted (to use such narrations) regarding the attributes of Allah (Most High) or Halal and Haram (i.e. legal rulings). (Imam Ibn Katheer, al-Baith al-Hatheeth).
In conclusion, not only do we have a sound narration (according to Imam al-Haythami) to prove the virtue of the 15th of Shaban, but we also have multiple weak narrations. These weak narrations would be sufficient in themselves to prove a Nafl matter such as this, however the existence of multiple narrations strengthens them. Thus, leaving no doubt regarding the fact that there is Hadith evidence to prove the virtue of the 15th Shaban.
And Allah (Most High) Knows Best.
– Answered by Shaykh Noorud-deen (19.03.2021)
Can weak Hadith strengthen each other?
Using Weak Hadith
Weak Hadith are used for supererogatory (Nafl) actions
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