Sunan an-Nasa'i 4411
سنن النسائي#4411SahihIt was narrated that Shaddad bin Aws said:"I heard the Messenger of Allah say: 'Allah, the Mighty and Sublime, has decreed proficiency in all things, so when you kill, kill well, and when you slaughter, slaughter well. Let one of you sharpen his blade and spare suffering to the animal he slaughters" (Sahih)
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: 43:51