Musnad Abu Ya'la al-Mawsili 155:17

Muhammad ibn Abdullah al-Arzi narrated to us, Abd al-Wahhab ibn Ata al-Khaffaf narrated to us, from Sa'id, from Qatadah, from Sa'id ibn al-Musayyib, from Abu Hurayrah, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "A prayer in this mosque of mine is better than a thousand prayers in any other mosque, except for the Sacred Mosque (al-Masjid al-Haram)."