Musannaf Ibn Abi Shayba 27:723

Yazid ibn Harun narrated to us, he said: Humayd informed us, from Anas, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The people are the outer garment (dithar), and the Ansar are the inner garment (shi'ar). The Ansar are my inner circle and my trusted confidants. And were it not for the Hijrah, I would have been a man from among the Ansar."