ذِكْرُ الْأَمْرِ بِوَفَاءِ نَذَرِ النَّاذِرِ إِذَا نَذَرَ مَا لِلَّهِ فِيهِ طَاعَةٌ
While the Prophet ﷺ was preaching a man was standing in the sun. He asked about him. They said: He is Abu Isra'il who has taken a vow to stand and not to sit, or go into shade, or speak, but to fast. Thereupon he said: Command him to speak, to go into the shade, sit and complete his fast. (Using translation from Abū Dāʾūd 3300)
بَيْنَمَا النَّبِيُّ ﷺ يَخْطُبُ إِذْ رَأَى رَجُلًا قَائِمًا فِي الشَّمْسِ فَسَأَلَ عَنْهُ فَقَالُوا هَذَا أَبُو إِسْرَائِيلَ نَذَرَ أَنْ يَقُومَ فِي الشَّمْسِ فَلَا يَقْعُدَ وَلَا يَسْتَظِلُّ وَلَا يَتَكَلَّمُ وَلَا يُفْطِرُ فَقَالَ «مُرُوهُ فَلْيَقْعُدْ وَلْيَسْتَظِلَّ وَلْيَتَكَلَّمْ وَلْيَصُمْ وَلْيُفْطِرْ (*)»