Musannaf Ibn Abi Shayba 17:1195

Ghundar narrated to us, from Shu'bah, from 'Amr ibn Murrah, from 'Abdullah ibn al-Harith, from Abu Kathir, from 'Abdullah ibn 'Amr, who said: A man stood up and said: "O Messenger of Allah, which Islam is best?" He said: "That the Muslims are safe from your hand and your tongue."