It is the oldest church fabric in the city, and within its precincts we stand amid the surroundings of early Christian congregations. For, partly in original forms, partly in imitations, we still find here a basilica's characteristic features: _the atrium_, or quadrangular court before the church; on three of its sides surrounded by _cloisters_; in its centre, the marble _phialé_ or fountain, for the purification of the gathering worshippers; the _narthex_, a pillared porch along the western façade, where catechumens and penitents, unworthy to enter the sanctuary itself, stood afar off; the interior area divided into _nave_ and _aisles_ by lines of columns; the semicircular _apse_ at the eastern extremity of the nave for altar and clergy; and _galleries_ on the other sides of the building to provide ample accommodation for large assemblies of faithful people.
Gyllius (_De Top. Constant._ l. iv. c. 9) describes the church as follows: 'Quod (monasterium) nunc non extat; aedes extat, translata in religionem Mametanam; in cujus vestibulo sunt quatuor columnae cum trabeatione egregie elaborata; in interiore parte aedium utrinque columnae sunt septem virides, nigris maculis velut fragmentis alterius generis lapidum insertis distinctae, quarum perimeter est sex pedum et sex digitorum. Denique earum ratio capitulorum, epistyliorum opere Corinthio elaborata, eadem est quae columnarum vestibuli. Supra illas sex existunt totidem columnae in parte aedis superiore. In area aedis Studianae est cisterna, cujus lateritias cameras sustinent viginti tres columnae excelsae Corinthiae.'
Gerlach (_Tagebuch_, p. 217; cf. pp. 359, 406) describes it under the style of the church of S. Theodore, for he confounds the monastery of Studius with that of the Peribleptos at Soulou Monastir: 'Das ist eine sehr hohe und weite Kirche (wie die unsern); hat zwei Reyhen Marmel-steiner Säulen mit Corinthischen Knäufen (capitellis), auff einer jeden Seiten sieben; auff deren jeden wieder ein andere Säule stehet. Der Boden ist mit lauter buntem von Vögeln und anderen Thieren gezierten Marmel auff das schönste gepflästert.' (This is a very lofty and broad church (like our churches). It has two rows of marble columns with Corinthian capitals, on either side seven; over each of which stands again another column. The floor is paved in the most beautiful fashion entirely with variegated marble, adorned with figures of birds and other animals.)
