Musnad Ahmad 2:118

I read to Abd al-Rahman ibn Mahdi: Malik, from Ibn Shihab, from Salim ibn Abdullah, from Ibn Umar, who said: A man from the companions of the Messenger of Allah, peace and blessings of Allah be upon him, entered the mosque on the day of Friday while Umar ibn al-Khattab was addressing the people. Umar said: "What time is this?" The man said: "O Commander of the Faithful, I returned from the market, then I heard the call (to prayer), so I did nothing more than perform ablution." Umar said: "And ablution as well? Yet you know that the Messenger of Allah, peace and blessings of Allah be upon him, used to command the ritual bath (ghusl)!"