Sunan an-Nasa'i 4131
سنن النسائي#4131SahihIt was narrated from Jarir that :During the Farewell Pilgrimage, the Messenger of Allah [SAW] asked the people to be quiet and listen, and said: "Do not revert to disbelievers after I am gone, striking the necks of one another (killing one another)
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 ZaiSahih - Agreed Upon
In-book reference: 37:166