Musannaf Ibn Abi Shayba 33:896

Yazid ibn Harun narrated to us, from Hammad ibn Salamah, from Thabit, who said: Mutarrif used to say: "O Allah, accept from me the prayer of a day. O Allah, accept from me the fasting of a day. O Allah, record for me a good deed." Then he would say: "Allah only accepts from the righteous."