Musnad Ahmad 30:2976

Yahya ibn Sa'id narrated to us, from Muhammad ibn 'Amr, Abu Salamah narrated to us, from Abu Hurairah, who said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "The most complete of the believers in faith are those of them with the best character, and the best of you are the best of you to your women."