Musannaf Ibn Abi Shayba 22:167

'Affan narrated to us, he said: Hassan bin Ibrahim narrated to us, from Sa'id bin Masruq, from Yazid bin Hayyan, from Zayd bin Arqam, he said: We entered upon him and said to him: "You have seen goodness; you accompanied the Messenger of Allah, may Allah bless him and grant him peace, and you prayed behind him." He said: "Yes, and he addressed us and said: 'I am leaving among you the Book of Allah; it is the rope of Allah. Whoever follows it is upon guidance, and whoever abandons it is upon misguidance.'"