Imam al-Sha'bi (may Allah have mercy on him) narrates from Sayyiduna al-Bara (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) delivered a sermon on the day of sacrifice and said: "The first thing on this day is to pray, and after that to go and sacrifice. Whoever does this has attained our way, and whoever sacrifices before praying, then that is meat for his family, but it is not a sacrifice." The narrator says: My maternal uncle, Sayyiduna Abu Burdah bin Niyar (may Allah be pleased with him), stood up and said: "O Messenger of Allah! I sacrificed before the prayer. But now I have a jadh'ah (a young animal) that is better than a two-toothed animal." He (peace and blessings be upon him) said: "Sacrifice it, but it will not suffice for anyone after you."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19109