Musnad Abu Ya'la al-Mawsili 246:21

Zuhayr narrated to us, Affan narrated to us, Abd al-Aziz ibn Muslim narrated to us, Husayn narrated to us, from Muhammad ibn Talhah, from Jubayr ibn Mut'im, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "A prayer in this mosque of mine exceeds any other mosque by a thousand prayers, except for the Sacred Mosque (al-Masjid al-Haram)."