Musnad Ahmad 288:18

Yahya ibn Adam narrated to us, Ibn al-Mubarak narrated to us, from al-Awza'i, from Hassan ibn Atiyyah, from Abu al-Ash'ath al-San'ani, from Aws ibn Aws al-Thaqafi, who said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "Whoever performs ghusl and causes ghusl to be performed on the day of Jumu'ah, and goes early and arrives early, and walks and does not ride, and draws near to the Imam, and listens and does not engage in idle talk, then for every step he takes, he shall have the reward of the deeds of a year, the fasting of it and the standing in prayer of it."