Musnad Abu Ya'la al-Mawsili 115:369

Ahmad narrated to us, Abu al-Nadr narrated to us, Shu'bah narrated to us, from Qatadah, who said: I heard Anas, from the Prophet (may Allah bless him and grant him peace), that he used to say: "There is no life except the life of the Hereafter, so forgive the Ansar and the Muhajirun."