Musnad Ahmad 28:574

Ali ibn Ishaq narrated to us, Abdullah narrated to us, Ibn Lahi'ah informed us, Al-Harith ibn Yazid informed me, from Ibn Hujayrah al-Akbar, from Abdullah ibn Amr, who said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "Indeed, the guided Muslim attains the rank of the one who fasts and prays throughout the night by the verses of Allah, the Almighty and Majestic, due to the nobility of his nature and the goodness of his character."