We owe our knowledge of Justinian’s works to Procopius, but his description of the St. Mary Church is so vague as to lead some writers to state that its position cannot be identified. Procopius[433] says that the “temple to the Virgin, ... called by natives the New Church,” was ordered to be built “on the most prominent of the hills.” It was begun by the Patriarch Elias, and completed by Justinian about 532 A. D. It was found that there was not enough flat ground to allow of the emperor’s design being carried out, without raising the foundations on vaults under about a quarter of the area towards the south-east, so that it was evidently on the narrower part of the Temple ridge. Antoninus Martyr tells us that a footprint of Christ was shown in this church, which later writers identify with the present Aḳṣa Mosque,[434] where the “footprint of Jesus” is still shown. In the twelfth century the Templars’ Church occupied the south part of this mosque, and had an apse on the east, the wall of which is still visible. It consisted of a nave and two aisles, and the mosque dome is still supported on fine columns which appear to be of the time of Justinian. The building stands partly on the rock and partly on the vaulted passage from the Double Gate, which passage is also of masonry attributable to the age of Justinian, its barrel vault being Byzantine. On the south-east the rock is 40 feet lower than the floor of the mosque, and the surface is banked up above it, and is partly supported by the west wall and the vaulted roof of the Triple Gateway. The site thus answers to that described by Procopius, and the Templars’ apse very probably marks the site of that which belonged to Justinian’s church, and which is described as being on the east. The building had two side apses--as was usual in this age--and on the west was a _narthex_, or narrow porch, with a square atrium or outer court, and beyond this again the western gates. The great apse was flanked by two tall pillars, and the church appears to have had a clerestory. The atrium, as well as the aisles, was adorned with large pillars, and it is supposed that some of the massive columns now used in the north part of the mosque have been cut down in height, and originally belonged to the church. They have Corinthian capitals, but are evidently not standing _in situ_,[435] and in style they are not as early as the pillars of Constantine’s basilica at Bethlehem.[436] We may suppose, therefore, that the new Church of the Virgin occupied what is called the “transept” of the Aḳṣa, thus including the “footprint of Christ” in its south-west part. It was thus about 160 feet long and 100 feet wide, with an atrium 100 feet square on the west. It resembled in plan the Holy Sepulchre basilica, except that it had three apses on the east instead of one large apse on the west. This building became the first mosque in Jerusalem a century after it was built. [Sidenote: ST. SOPHIA]