The Desert Fathers emphasized the light of the ascetic experience, and related it to the light of the Transfiguration - a theme developed further by Evagrius Ponticus in the 4th century. Around the same time Saint Gregory of Nyssa and later Pseudo-Dionysius the Areopagite were developing a theology of light which then influenced Byzantine meditative and mystical traditions such as the Tabor light and theoria. The iconography of the transfiguration continued to develop in this time period, and there is a sixth-century symbolic representation in the apse of the Basilica of Sant'Apollinare in Classe and a well known depiction at Saint Catherine's Monastery on Mount Sinai in Egypt.