The Prophet ﷺ said, "Whoever throws himself off a mountain and kills himself will be in the Fire of Hell, throwing himself down forever, abiding there eternally. Whoever drinks poison and kills himself, his poison will be in his hand, sipping it in the Fire of Hell, abiding there forever, eternally. Whoever kills himself with a piece of iron…"Then the chain broke off at something. Khalid said, "His piece of iron will be in his hand, stabbing himself with it in his belly in the Fire of Hell, abiding there forever, eternally."
أخبرنا محمد بن عبد الأعلى قال حدثنا خالد قال حدثنا شعبة عن سليمان سمعت ذكوان يحدث
عن النبي ﷺ قال من تردى من جبل فقتل نفسه فهو في نار جهنم يتردى خالدا مخلدا فيها أبدا ومن تحسى سما فقتل نفسه فسمه في يده يتحساه في نار جهنم خالدا مخلدا فيها أبدا ومن قتل نفسه بحديدة ثم انقطع علي شيء خالد يقول كانت حديدته في يده يجأ بها في بطنه في نار جهنم خالدا مخلدا فيها أبدا
Reported by Bukhari, Medicine, chapter on drinking poison and medicine made from it, and what is feared from it and what is impure, etc., hadith 109 from hadith 5778, and Muslim, Faith, chapter on the explanation of the severity of the prohibition of a person killing himself, hadith of Khalid bin Harith with the same wording, and it is in Al-Kubra, hadith 2092. Sulayman is Ibn Mihran Amash.