Musannaf Ibn Abi Shayba 27:749

Al-Fadl ibn Dukayn narrated to us, from Abdullah ibn Mubashir, from Zayd ibn Abi ‘Attab, who said: Mu’awiyah stood upon the pulpit and said: The Prophet, may Allah bless him and grant him peace, said: "The people are followers of Quraysh in this matter; their best in the Age of Ignorance are their best in Islam, if they attain understanding (fiqh)." By Allah, were it not that Quraysh would become insolent, I would have informed them of what their best have with Allah.