Musnad Ahmad 30:3378

Yazid narrated to us, Muhammad informed us, from Abu Salamah, from Abu Hurairah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Were it not for the migration (Hijrah), I would have been a man from the Ansar. And if the people were to travel through a valley or a mountain pass, and the Ansar were to travel through a valley or a mountain pass, I would travel through the valley and mountain pass of the Ansar."