Ibn ‘Abbas said:While the Prophet was preaching a man was standing, so he asked about him and was told that he was Abu Isra’il who had taken a vow to stand and not to sit, or go into the shade, or speak, but to fast. Thereupon the Prophet said, “Command him to speak, go into the shade, sit and complete his fast.” Bukhari transmitted it.
Hadith Referenceمشكوة المصابيح / كتاب الإيمان والنذور / 3430
Hadith Gradingالألبانی:صَحِيحٌ | زبیر علی زئی:صحيح
Hadith Takhrij´تحقيق و تخريج: محدث العصر حافظ زبير على زئي رحمه الله` «رواه البخاري (6704)»