Musnad Ahmad 30:2993

Yahya narrated to us, Ismail narrated to us, he said: Ziyad, the freed slave of Banu Makhzum, narrated to us, from Abu Hurairah, from the Prophet, may Allah bless him and grant him peace, who said: "There is not one among you who will enter Paradise by his deeds." It was said: "Not even you, O Messenger of Allah?" He said: "Not even me, unless Allah covers me with mercy and grace from Him."