Musnad Abu Ya'la al-Mawsili 42:119

Abu Bakr narrated to us, Abdullah ibn Idris narrated to us, from Muhammad ibn Ishaq, from Asim ibn Umar ibn Qatadah, from Mahmud ibn Labid, from Abu Sa’id, who said: The Prophet, may Allah bless him and grant him peace, said: "The Ansar are the inner garment (shi'ar), and the people are the outer garment (dithar). And were it not for the Hijrah, I would have been a man from among the Ansar."