Muwatta Malik, Book 50, Hadith 13 (USC-MSA)

Yahya related to me from Malik that Yahya ibn Said said, "I heard that Sad ibn Zurara cauterized himself because of a pain in the throat accompanied by blood and he died."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، قَالَ بَلَغَنِي أَنَّ سَعْدَ بْنَ زُرَارَةَ، اكْتَوَى فِي زَمَانِ رَسُولِ اللَّهِ صلى الله عليه وسلم مِنَ الذُّبَحَةِ فَمَاتَ ‏.‏

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also referenced under: Book 50, Hadith 1726 (In-Book)