Musnad Abu Ya'la al-Mawsili 6:16

Abu al-Rabi' narrated to us, Hammad narrated to us, from 'Asim, from Mus'ab ibn Sa'd, who said: I said to my father, "O my father, have you seen His saying: 'Those who are heedless of their prayer' (al-Ma'un)? Which of us does not become heedless? Which of us does not speak to himself?" He said, "It is not that. It is only the wasting of the time; he plays until he wastes the time."