Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) said: I was present with the Messenger of Allah (peace and blessings be upon him) for Eid al-Adha at the prayer ground. When he finished his sermon and came down from his pulpit, his ram was brought to him, and he slaughtered it and said: 'Bismillah wallahu akbar' (In the name of Allah, and Allah is the Greatest). "This is on behalf of me and on behalf of those of my Ummah who have not sacrificed."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19183