Khutba of Zainab, Ali's Daughter, in Yazid's Court

From tafsir by Ibn Kathir
Ali bin Abi Talhah reported that Ibn Abbas said: do not say (anything of which you have no knowledge).‘’ Al-`Awfi said: “Do not accuse anyone of that of which you have no knowledge”

Tafsir Ibn Kathir - Quran Tafsir - Do not speak without Knowledge