Sahih Muslim , Book 40, Hadith 6811 (USC-MSA) ⓘ
Abu Huraira reported Allah's Apostle as saying: The fire which sons of Adam burn is only one-seventieth part of the Fire of Hell. His Companions said: By Allah, even ordinary fire would have been enough (to burn people). Thereupon he said: It is sixty-nine parts in excess of (the heat of) fire in this world each of them being equivalent to their heat.
حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا الْمُغِيرَةُ، - يَعْنِي ابْنَ عَبْدِ الرَّحْمَنِ الْحِزَامِيَّ - عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " نَارُكُمْ هَذِهِ الَّتِي يُوقِدُ ابْنُ آدَمَ جُزْءٌ مِنْ سَبْعِينَ جُزْءًا مِنْ حَرِّ جَهَنَّمَ " . قَالُوا وَاللَّهِ إِنْ كَانَتْ لَكَافِيَةً يَا رَسُولَ اللَّهِ . قَالَ " فَإِنَّهَا فُضِّلَتْ عَلَيْهَا بِتِسْعَةٍ وَسِتِّينَ جُزْءًا كُلُّهَا مِثْلُ حَرِّهَا " .
also referenced under: Book 53, Hadith 34 (In-Book) & Hadith 2843 (Reference)