Musnad Ahmad 30:2186

Muhammad ibn Ja'far narrated to us, Shu'bah narrated to us, from Muhammad ibn Ziyad, from Abu Hurairah, who said: The Messenger of Allah, Abu al-Qasim, said: "If the Ansar were to travel through a valley or a mountain pass, I would travel through the valley of the Ansar. And were it not for the Hijrah (emigration), I would have been a man from among the Ansar." He said: Abu Hurairah used to say: "He did not wrong [them]—may my father and mother be sacrificed for him—for they sheltered him and supported him," and another word.