Musnad Ahmad 26:330

'Abd al-Razzaq narrated to us, Sufyan informed us, from al-A'mash, from 'Abd Allah ibn Murrah, from Abu al-Ahwas, who said: 'Abd Allah said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "I disassociate myself from every intimate friend (khalil) because of his intimate friendship. And if I were to take an intimate friend, I would have taken the son of Abu Quhafah as an intimate friend. But your companion is the intimate friend of Allah, the Almighty and Majestic."