Musannaf Ibn Abi Shayba 3:1074

Abu Bakr narrated to us, he said: Abu Khalid narrated to us, from al-A’mash, from Isma’il ibn Raja’, from Aws ibn Dam’aj, from Abu Mas’ud al-Ansari, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The one who leads the people in prayer is the one among them who is most proficient in the Book of Allah. If they are equal in recitation, then the one among them who is most knowledgeable of the Sunnah. If they are equal in the Sunnah, then the one among them who is earliest in migration. If they are equal in migration, then the one among them who is earliest in Islam." "And a man should not lead another man in prayer in his place of authority, nor should he sit in his house on his seat of honor, except with his permission."