The description of the (Hell) Fire and the fact that it has already been created
حَدَّثَنِي عَبْدُ اللَّهِ بْنُ مُحَمَّدٍ، حَدَّثَنَا أَبُو عَامِرٍ، حَدَّثَنَا هَمَّامٌ، عَنْ أَبِي جَمْرَةَ الضُّبَعِيِّ، قَالَ كُنْتُ أُجَالِسُ ابْنَ عَبَّاسٍ بِمَكَّةَ، فَأَخَذَتْنِي الْحُمَّى، فَقَالَ أَبْرِدْهَا عَنْكَ بِمَاءِ زَمْزَمَ، فَإِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " الْحُمَّى مِنْ فَيْحِ جَهَنَّمَ فَأَبْرِدُوهَا بِالْمَاءِ ". أَوْ قَالَ " بِمَاءِ زَمْزَمَ ". شَكَّ هَمَّامٌ.
Narrated Abu Jamra Ad-Dabi: I used to sit with Ibn `Abbas in Mecca. Once I had a fever and he said (to me), "Cool your fever with Zamzam water, for Allah's Messenger (ﷺ) said: 'It, (the Fever) is from the heat of the (Hell) Fire; so, cool it with water (or Zamzam water).