Musannaf Ibn Abi Shayba 22:98

Ibn Numayr narrated to us, he said: Aban ibn Ishaq narrated to us, he said: A man from Bajilah narrated to me, he said: Jundub al-Bajali went out on a journey of his. He said: So some people from his tribe went out with him until, when they were at the place where they bid farewell to one another, he said: O my people, upon you is the fear of Allah. Upon you is this Qur’an, so adhere to it despite whatever hardship and poverty there may be. For it is a light in the dark night and a guidance in the day.