Qutbah bin Malik narrates: One of the governors reviled Sayyiduna Ali (may Allah be pleased with him), so Sayyiduna Zayd bin Arqam (may Allah be pleased with him) stood up towards him and said: "Listen! I know well that the Messenger of Allah (peace and blessings be upon him) forbade reviling the dead, so why do you revile Ali when he has passed away?"
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4954
The paternal uncle of Ziyad bin Ilaqah narrates that Mughirah bin Shu'bah (may Allah be pleased with him) (said something improper about Sayyiduna Ali (may Allah be pleased with him)), so Sayyiduna Zayd bin Arqam (may Allah be pleased with him) stood up towards him and said: "O Mughirah! Do you not know that the Messenger of Allah (peace and blessings be upon him) forbade speaking ill of the dead? So why do you speak ill of Ali when he has passed away?"
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4955
Ziyad bin Ilaqah narrates that a man spoke ill of Sayyiduna Ali bin Abi Talib (may Allah be pleased with him), so Sayyiduna Zayd bin Arqam (may Allah be pleased with him) said to him: "Do you not know that the Messenger of Allah (peace and blessings be upon him) used to forbid speaking ill of the dead?"
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4956