Hadith: Whoever throws himself from a mountain and kills himself will be in Hellfire, falling down into it and abiding therein eternally forever

عَنْ أَبِي هُرَيْرَةَ رَضِيَ اللَّهُ عَنْهُ عَنِ النَّبِيِّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ قَالَ:
«مَنْ تَرَدَّى مِنْ جَبَلٍ فَقَتَلَ نَفْسَهُ فَهُوَ فِي نَارِ جَهَنَّمَ يَتَرَدَّى فِيهِ خَالِدًا مُخَلَّدًا فِيهَا أَبَدًا، وَمَنْ تَحَسَّى سُمًّا فَقَتَلَ نَفْسَهُ فَسُمُّهُ فِي يَدِهِ يَتَحَسَّاهُ فِي نَارِ جَهَنَّمَ خَالِدًا مُخَلَّدًا فِيهَا أَبَدًا، وَمَنْ قَتَلَ نَفْسَهُ بِحَدِيدَةٍ فَحَدِيدَتُهُ فِي يَدِهِ يَجَأُ بِهَا فِي بَطْنِهِ فِي نَارِ جَهَنَّمَ خَالِدًا مُخَلَّدًا فِيهَا أَبَدًا».
[صحيح] - [متفق عليه] - [صحيح البخاري: 5778]

Abu Hurayrah (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said:
"Whoever throws himself from a mountain and kills himself will be in Hellfire, falling down into it and abiding therein eternally forever; whoever drinks poison and kills himself will be carrying his poison in his hand and drinking it in Hellfire, wherein he will abide eternally forever; and whoever kills himself with a piece of iron will be carrying his piece of iron in his hand and stabbing his abdomen with it in Hellfire wherein he will abide eternally forever."
[Authentic hadith] - [Narrated by Bukhari & Muslim] - [Sahih Bukhari - 5778]

Explanation

The Prophet (may Allah's peace and blessings be upon him) warned against intentionally taking one's own life in this world, stating that such a person will be punished in Hellfire on the Day of Judgment in the same manner by which he ended his life, as a fitting recompense. If someone threw himself off a mountain and died, he will continuously fall from the mountains of Hellfire into its valleys, abiding therein forever. If someone drank poison to kill himself, he will have that poison in his hand, drinking it repeatedly in Hellfire, eternally. And if someone stabbed himself in the belly with a piece of iron, he will have that piece of iron in his hand, stabbing his belly repeatedly in Hellfire, abiding therein forever.