وَحَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، وَابْنُ، بَشَّارٍ - وَاللَّفْظُ لاِبْنِ الْمُثَنَّى - قَالاَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، قَالَ سَمِعْتُ أَبَا إِسْحَاقَ، يَقُولُ سَمِعْتُ النُّعْمَانَ بْنَ بَشِيرٍ، يَخْطُبُ وَهْوَ يَقُولُ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏"‏ إِنَّ أَهْوَنَ أَهْلِ النَّارِ عَذَابًا يَوْمَ الْقِيَامَةِ لَرَجُلٌ تُوضَعُ فِي أَخْمَصِ قَدَمَيْهِ جَمْرَتَانِ يَغْلِي مِنْهُمَا دِمَاغُهُ ‏"‏ ‏.‏

Nu'man b. Bashir was delivering an address and saying: I heard the Messenger of Allah (PBUH) say: the least suffering for the inhabitants of Hell on the Day of Resurrection would be for the man under whose soles would be placed two embers and his brain would boil on account of them. Translation Not Available

Book Ref: Sahih Muslim Book 1 Hadith 414
Web Ref:  Sahih Muslim Book 1 Hadith 213 a