Tamim bin Salamah (may Allah have mercy on him) said: Ibn al-Zubayr (may Allah be pleased with him) came out on Eid al-Adha and saw the people, and they were not saying the takbir. He said: What is the matter with them that they do not say the takbir? By Allah, the Companions used to say it. We have seen armies in which a man on one side would say the takbir, then the one next to him, until the army would resound with the takbir. Indeed, the difference between you and them is like the distance between the lowest earth and the highest heaven.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة العيدين / 6133