Musnad Ahmad 30:1822

Qutaybah ibn Sa'id narrated to us, he said: Ibn Lahi'ah narrated to us, from Abu Yunus, from Abu Hurairah, who said: "I have not seen anything more beautiful than the Messenger of Allah, may Allah bless him and grant him peace; it is as if the sun were running across his face. And I have not seen anyone faster in his walking than the Messenger of Allah, may Allah bless him and grant him peace; it is as if the earth were being folded for him. We would exert ourselves, while he was unconcerned."