Musnad Ahmad 626:46

Isma'il narrated to us, Khalid al-Hadhdha' narrated to us, Ibn Ashwa' narrated to me, from al-Sha'bi, who said: The scribe of al-Mughirah ibn Shu'bah narrated to me, saying: Mu'awiyah wrote to al-Mughirah ibn Shu'bah: "Write to me something you heard from the Messenger of Allah, may Allah bless him and grant him peace." So he wrote to him: "I heard the Messenger of Allah, may Allah bless him and grant him peace, saying: 'Indeed, Allah has disliked for you: gossip (lit. "it was said and he said"), wasting wealth, and excessive questioning.'"