The Book of Sacrifices (Kitab Al-Adahi)

Muslim :: Book 22 : Hadith 4834

Anas b. Malik reported that Allah's Messenger (may peace be upon him) offered the 'Id prayer and then delivered the sermon giving the command: He who slaughtered the animal before prayer should slaughter (another animal as a sacrifice). The rest of the hadith is the same.

Source materials are from the University of Southern California MSA site
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