Muwatta Malik 1723
موطأ مالك#1723Sahihوَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، قَالَ بَلَغَنِي أَنَّ سَعْدَ بْنَ زُرَارَةَ، اكْتَوَى فِي زَمَانِ رَسُولِ اللَّهِ صلى الله عليه وسلم مِنَ الذُّبَحَةِ فَمَاتَ .
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
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Salim al-HilaliSahih Lighairihi
In-book reference: 50:13