Sunan an-Nasa'i 4865
سنن النسائي#4865SahihIt was narrated that Sa'eed bin Jubair said:"I said to Ibn Abbas . 'Can a person who killed a believer intentionally repent?' He said: 'No.' Irecited the Verse from Al-Furqan to him: And those who invoke not any other ilah (god) along with Allah, nor kill such person a Allah has forbidden, except but right. He said: 'This Verse was revealed in Makkah and was abrogated by a verse that was revealed in Al-Madinah: And whoever kills a believer intentionally, his recompense is Hell
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiHasan
In-book reference: 45:160