Musannaf Ibn Abi Shayba 22:104

Katheer ibn Hisham narrated to us, from Ja’far ibn Burqan, who said: Al-Akhnas ibn Abi Al-Akhnas narrated to us, from Zubayd Al-Muradi, who said: I witnessed Ibn Mas’ud as a preacher, and he said: "Adhere to the Quran and hold fast to it." He then began to clasp his hands together, as if he were grasping the rope of something.