Musnad Ahmad 30:2488

Yahya ibn Sa'id al-Qattan narrated to us, from Habib ibn al-Shahid, from 'Ata', who said: Abu Hurayrah said: "In every prayer, there is recitation. So, whatever the Messenger of Allah (peace and blessings of Allah be upon him) made us hear, we have made you hear; and whatever he kept hidden from us, we have kept hidden from you."