Musnad Abu Ya'la al-Mawsili 117:43

Hadaba bin Khalid and Bishr bin al-Walid al-Kindi narrated to us, they said: Suhayl bin Abi Hazm narrated to us, from Thabit, from Anas, that the Messenger of Allah (peace be upon him) said regarding this verse: "He is the Lord of righteousness and the Lord of forgiveness." The Messenger of Allah (peace be upon him) said: Your Lord says: "I am worthy that I should be feared, so let no one be associated with Me. And I am worthy, for whoever fears that he should associate anyone with Me, that I should forgive him."