Sahih Bukhari Volume 4, Book 56, Hadith Number 731.

Narated By ‘Aisha : Once Hassan bin Thabit asked the permission of the Prophet to lampoon (i.e. compose satirical poetry defaming) the infidels. The Prophet said, “What about the fact that I have common descent with them?” Hassan replied, “I shall take you out of them as a hair is taken out of dough.”

Narrated ‘Urwa: I started abusing Hassan in front of ‘Aisha, whereupon she said. “Don’t abuse him, for he used to defend the Prophet (with his poetry).”