Musannaf Ibn Abi Shayba 27:692

Abu Mu'awiyah narrated to us, from al-A'mash, from 'Amr ibn Murrah, from Abu al-Bakhtari, who said: They said to 'Ali, "Tell us about Salman." He said, "He attained the first knowledge and the last knowledge. He is a sea whose depth cannot be reached. He is of us, the People of the House."