Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
tirmidhi:2575ʿAbd b. Ḥumayd

"While he was on the pulpit – the pulpit of Al-Basrah – ʿUtbah bin Ghazwain narrated that the Messenger of Allah ﷺ said: “Indeed a giant rock can be thrown from the brink of Hell and it will continue to fall into it for seventy years without reaching the bottom of it.”.He said: “ʿUmar used to say:'Increase in your remembrance of the Fire, for its heat is extreme, its bottom is distant, and its whips are of Iron.'” (Sahih)  

الترمذي:٢٥٧٥حَدَّثَنَا عَبْدُ بْنُ حُمَيْدٍ حَدَّثَنَا حُسَيْنُ بْنُ عَلِيٍّ الْجُعْفِيُّ عَنْ فُضَيْلِ بْنِ عِيَاضٍ عَنْ هِشَامٍ عَنِ الْحَسَنِ قَالَ قَالَ عُتْبَةُ بْنُ غَزْوَانَ عَلَى مِنْبَرِنَا هَذَا مِنْبَرِ الْبَصْرَةِ

عَنِ النَّبِيِّ ﷺ قَالَ إِنَّ الصَّخْرَةَ الْعَظِيمَةَ لَتُلْقَى مِنْ شَفِيرِ جَهَنَّمَ فَتَهْوِي فِيهَا سَبْعِينَ عَامًا وَمَا تُفْضِي إِلَى قَرَارِهَا قَالَ وَكَانَ عُمَرُ يَقُولُ أَكْثِرُوا ذِكْرَ النَّارِ فَإِنَّ حَرَّهَا شَدِيدٌ وَإِنَّ قَعْرَهَا بَعِيدٌ وَإِنَّ مَقَامِعَهَا حَدِيدٌ  

قَالَ أَبُو عِيسَى لاَ نَعْرِفُ لِلْحَسَنِ سَمَاعًا مِنْ عُتْبَةَ بْنِ غَزْوَانَ وَإِنَّمَا قَدِمَ عُتْبَةُ بْنُ غَزْوَانَ الْبَصْرَةَ فِي زَمَنِ عُمَرَ وَوُلِدَ الْحَسَنُ لِسَنَتَيْنِ بَقِيَتَا مِنْ خِلاَفَةِ عُمَرَ

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Collected by Suyūṭī
suyuti:5664a
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السيوطي:٥٦٦٤a

"إِنَّ الصَّخْرَةَ الْعَظِيمَةَ لَتُلْقَى من شَفِيرِ جَهَنَّم، فَتَهْوى بها سَبْعِينَ عَامًا مَا تُفْضِي إِلى قَرَارِها ".  

[ت] الترمذي منقطع عن عتبة بن غزوان
suyuti:2-3086bal-Ḥsn
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السيوطي:٢-٣٠٨٦b

"عن الحسن قال: كَان عُمَرُ يقولُ أَكْثِرُوا ذِكْرَ النَّارِ، فإنَّ حَرَّهَا شَدِيدٌ، وإِنَّ قَعْرَهَا بَعِيدٌ وإِنَّ مَقَامِعَهَا حَدِيدٌ".  

[ش] ابن أبى شيبة