The medieval view of the universe as entirely theophany, manifestation of God; and hierarchy, the ordered participation of all beings to God, could not conceive of an opposition between subject and object. Aut lux hic nata est aut capta hic libera regnat, “here the light is born, or here, captive, it freely reigns,” may be read in the vestibule of a chapel at Ravenna: that not yet created golden light enclosing heaven and earth in the selfsame unity where everything became perceptible at a single glance. From an infinite distance descended the Word, filling the void and becoming the universe; while from below, the rising wave of adoration gradually divested created beings of their terrestrial weight, introducing finiteness and multiplicity into the realm of immutable crystalline eternity. Light as the most efficacious means of sanctification, as the surest way of negating the restrictive power of thingness: this was the basis on which Robert Grosseteste formulated an entire light-cosmogony. The stained glass masters of the cathedrals of the West, and the Byzantine mosaicists held the same view. The description of Saint Sophia, made in the 6th century by Paul the Silentiaire, leads us right into the heart of this magical world of light:
The apse is like a peacock, whose plumage has a hundred eyes. One's sight is blinded by the brilliant light emanating from the golden immensity of the vault. It is a Latin and barbaric display at the same time. The altar is of gold; it rests on golden columns and golden supports; other than gold there are only sparkling gems. In the evening so much light is reflected from the temple that you would think it to be a nocturnal sun. Resplendent night laughs like dawn; it too seems to have rosy feet. The navigator needs no other lighthouse; he need only gaze at the radiant temple.