Musannaf Ibn Abi Shayba 23:42

'Atham ibn 'Ali narrated to us, from al-A'mash, from Abu Ishaq, from Hani' ibn Hani', who said: We were sitting with 'Ali, and 'Ammar entered. He said: "Welcome to the good, the purified. I heard the Messenger of Allah (peace and blessings of Allah be upon him) say: 'Indeed, 'Ammar is filled with faith to his very marrow.'"