Al-Walid bin Sari' narrates: On the day of Eid we went out (to perform the Eid prayer) with the Commander of the Believers, Sayyiduna Ali bin Abi Talib (may Allah be pleased with him). Some of his companions asked him: "O Commander of the Believers! What is your view about offering (voluntary) prayer on the day of Eid before or after the Eid prayer?" Sayyiduna Ali (may Allah be pleased with him) gave them no answer. Then some other people came and asked the same question as the earlier ones, and Sayyiduna Ali (may Allah be pleased with him) gave them no answer either. When we reached the Eid prayer ground, he led the people in prayer and said seven and five takbirs; then he addressed the people with the sermon, then came down from the pulpit and mounted his ride. The people said: "O Commander of the Believers! These are some people offering (voluntary) prayer." Sayyiduna Ali (may Allah be pleased with him) said: "What can I do? You asked me about the Sunnah: the Prophet (peace and blessings be upon him) did not offer any voluntary prayer before this prayer or after it. Whoever wishes may do it, and whoever wishes may leave it. Do you think that I would forbid people who are praying, and so become like the one (mentioned in the Qur'an) who prevented a servant when he prayed?"
Al-Bazzar recorded it, and he says: This narration is reported from Sayyiduna Ali (may Allah be pleased with him) only through this chain. (Allamah Haythami says:) I say: Its chain contains a narrator whom I do not know.