Musannaf Ibn Abi Shaybah

Hazrat Fatimah bint Qais (may Allah be pleased with her) narrates that the Noble Prophet (peace and blessings be upon him) said: This is Tayyibah (pure), meaning Madinah Munawwarah. By the One in Whose hand is the soul of Muhammad, there is no wide or narrow path in it except that there is an angel appointed over it until the Day of Judgment, standing with a drawn sword.