Jami` at-Tirmidhi 2043
جامع الترمذي#2043SahihAbu Hurairah narrated (from the Messenger of Allah (s.a.w)):"Whoever kills himself with (an instrument of)iron, he will come on the Day Of Judgment with his iron in his hand, to continually stab himself in his stomach with it, in the fire of Jahannam, dwelling in that state eternally. And whoever kills himself with poison, then his poison will be in his hand, to continually take it in the Fire of Jahannam, dwelling in that state eternally
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 28:8