Musnad Ahmad 1118:19

Mu'awiyah ibn 'Amr narrated to us, Rushdin narrated to us, he said: Mu'awiyah ibn Sa'id al-Tujibi narrated to me, from the one who narrated to him, from Fudalah ibn 'Ubayd, from the Prophet, peace and blessings of Allah be upon him, that he said: "The servant is secure from the punishment of Allah, as long as he seeks forgiveness from Allah."