What is the ruling of fasting on 15th Shaabaan?
Is it Sunnah to fast on the 15th of Shaabaan?
Or is it a Bidah?
Wa’alaykum as Salam wa rahmatullahi wa barakatuhu,
Since the narration in which the fasting of the fifteenth of Shabaan is extremely weak, the fast cannot be classified as a Sunnah. Rather, it will be regarded as Mustahab to fast on the fifteenth of Shabaan. (Fatawa Darul Ulum Zakariyya, 3/323).
The fast will only be regarded as a Bidah if:
1) People regard the specific fast of the fifteenth of Shabaan to be a Sunnah.
2) People criticise and look down at a person who does not fast.
However, if the weak narration of Sunan Ibn Majah (page 99), or the Ahadith of fasting on Ayaam Beedh (13th, 14th and 15th of EVERY month), or the general Ahadith of fasting in Shabaan are used as the basis of fasting on the fifteenth, then it will not be regarded as Bidah (innovation)
And Allaah Ta’aala knows best
Ismail Moosa (Mufti)
المرغوبات من الصيام انواع اولها صوم المحرم والثاني صوم رجب والثالث صوم شعبان (الهندية 1/202)