Musnad Ahmad 30:2269

Qutaybah ibn Sa'id narrated to us, he said: Ya'qub ibn 'Abd al-Rahman ibn Muhammad ibn 'Abd al-Qari informed us, from 'Amr ibn Abi 'Amr, from Sa'id al-Maqburi, from Abu Hurayrah, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "I was sent in the best of the generations of the children of Adam, generation after generation, until I was from the generation in which I am."