Sahih al-Bukhari 5545

Muḥammad ibn Bashshār narrated to us: Ghundar narrated to us: Shuʿbah narrated to us, from Zubayd al-Iyāmī, from al-Shaʿbī, from al-Barāʾ (may God be pleased with him), who said: The Prophet ﷺ said: “The first thing we will do on this day of ours is pray, then return and slaughter. Whoever does that has followed our Sunnah. Whoever slaughtered before that has only provided meat for his family; it has nothing to do with the sacrificial rite.” Abū Burdah ibn Niyār stood up, having slaughtered, and said, “I have a young sheep.” He said: “Slaughter it, but it will not suffice for anyone after you.” Muṭarrif reported from ʿĀmir, from al-Barāʾ, that the Prophet ﷺ said: “Whoever slaughters after the prayer has completed his rite and followed the Sunnah of the Muslims.”