Abu Ubaid (may Allah have mercy on him) says that on both occasions of Eid al-Fitr and Eid al-Adha, I had the opportunity to be present with Sayyiduna Uthman and Sayyiduna Ali (may Allah be pleased with them both). Both of these noble companions would first lead the prayer, and after completing the prayer, they would advise the people. I heard both of them say that the Messenger of Allah (peace and blessings be upon him) forbade fasting on these two days.