Sahih Muslim | Book 22 | Hadith Number 4821

Narrated by Jundab al-Bajali
Jundab al-Bajali reported: I saw Allah's Messenger (may peace be upon him) observing ('Id) prayer on the Day of Sacrifice (10th of Dhu'l-Hijja) and then delivering a sermon and he said: He who sacrificed the (animal) before offering ('Id) prayer, he should offer again in its stead, and he who did not sacrifice the animal should slaughter it by reciting the name of Allah.