Musnad Ahmad 2:245

Abu Sa’id narrated to us, Hammad bin Zayd narrated to us, from ‘Amr bin Dinar, the freed slave of the family of Zubayr, from Salim, from his father, from ‘Umar, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever says in a marketplace: 'There is no god but Allah alone, He has no partner; to Him belongs the dominion, and to Him belongs the praise; in His hand is all good; He gives life and causes death, and He is capable of all things,' Allah will record for him a million good deeds, and will erase from him a million bad deeds, and will build for him a house in Paradise."