Musnad Ahmad 30:1962

Aswad narrated to us, Sharik narrated to us, from Ibn Umayr—meaning Abd al-Malik—from Abu Salamah, from Abu Hurairah, from the Prophet, may God bless him and grant him peace, that he said upon the pulpit: "The most poetic verse the Arabs have ever spoken is: 'Indeed, everything except God is false.' And Umayyah ibn Abi al-Salt was on the verge of becoming a Muslim."