Musannaf Ibn Abi Shayba 22:187

Ubaydah ibn Humayd narrated to us, from Mansur, from Hilal ibn Yasaf, from Farwah ibn Nawfal, who said: Khabbab ibn al-Aratt said, and I was walking with him from the mosque to his house: "If you are able to draw near to Allah, then do so, for you will not draw near to Him with anything more beloved to Him than His speech."