Musnad Ahmad 30:2724

Hajjaj narrated to us, he said: Ibn Jurayj narrated to us, he said: Al-‘Ala’ ibn ‘Abd al-Rahman ibn Ya‘qub narrated to me, from Ibn Darah, the freed slave of ‘Uthman, who said: We were at al-Baqi‘ with Abu Hurayrah when we heard him say: "I am the most knowledgeable of people regarding the intercession of Muhammad, may Allah bless him and grant him peace, on the Day of Resurrection." He said: So the people crowded around him and said: "Tell us, may Allah have mercy on you." He said: He says: "O Allah, forgive every believing servant who met You, believing in me, not associating anything with You."