The inside strikes for the stately impressiveness and for the extraordinary game of volumes chased by arcades and domes, and of color, the gilded of the mosaics, while the floors with geometric patterns complete the whole. The space is divided in three aisles and decorated columns with Byzantine capitals;
  above there are the matroneis. The ceilings are decorated with mosaics on gold bottom that date back partly to the twelfth-thirtieth century, partly to a following epoch and they narrate, following a precise sketch, the Exaltation of the church of Christ, the Venetian Church and St. Mark. The domes decorated with mosaic constitute the greatest beauty of the inside. They dates back to the thirtieth century and they narrate the preaching of the Apostles, the Passion, Christ benedictory with the Saints. The mosaics of the dome of the presbytery with images of Christ and the Prophets date back to the end of the twelfth century; the mosaics between the windows have been realized before the 1105, the year of the fire.