Musnad Abu Ya'la al-Mawsili 157:2

Al-Hasan ibn Isma'il al-Basri narrated to us, Ibrahim ibn Sa'd narrated to us, from al-Zuhri, from Abu 'Ubayd, the freed slave of 'Abd al-Rahman ibn 'Awf, from Abu Hurayrah, that the Messenger of Allah (may Allah bless him and grant him peace) said: "There is no one whom his deeds will cause to enter Paradise." They said: "Not even you, O Messenger of Allah?" He said: "Not even me, unless Allah covers me with mercy from Him."