The Cappella Arcivescovile or di Sant’Andrea, which can be accessed through the museum of Palazzo Arcivescovile, is on the first floor.
It is the only Orthodox monument built by Bishop Peter II, as a private oratory of the Catholic bishops during the reign of Theodoric. Bishops have prayed and celebrated here from Antiquity to the present day.
Built at the beginning of the fifth century, the chapel was dedicated to Christ and the whole decorative scheme glorifies this figure in an anti-Arian interpretation.
The presence of the Saviour as a warrior with the cross borne on his shoulder, his monogram and his face, dominate in various parts of the chapel. The images of martyrs, apostles and evangelists also contribute to underline the theme of glorification, as an affirmation of Catholic orthodoxy.
Likewise, the Latin inscription in the vestibule, which reads: “Either light was born here or it was captured, [either way, here it] reigns freely” (“Aut lux hic nata est aut capta hic libera regnat”), most likely referring to the Orthodox light, is in sharp contrast to Arianism and, at the same time, is reflected in the radiance of the mosaics.
Later, the chapel was named after Saint Andrew, whose relics arrived here from Constantinople around the middle of the sixth century.