Musannaf Ibn Abi Shayba 33:1448

Zayd ibn al-Hubab narrated to us, he said: Abdullah ibn Sumayt narrated to us, from Budayl ibn Maysarah al-Uqayli or Matar al-Warraq, that he said: "Whoever knows his Lord loves Him, and whoever sees the world for what it is, becomes ascetic regarding it. The believer does not become heedless until he engages in vain play, and when he reflects, he becomes sorrowful."