Musnad Ahmad 31:370

Mu'awiyah ibn Hisham narrated to us, Shayban narrated to us, from Firas, from 'Atiyyah, from Abu Sa'id, who said: The Prophet of Allah, may Allah bless him and grant him peace, said: "It will be said to the companion of the Qur'an on the Day of Resurrection, when he enters Paradise: 'Recite and ascend.' So he will recite and ascend one degree for every verse, until he recites the last thing that is with him."