The wall that separates two worlds [both the visible and the invisible] in an iconostasis. One might mean by the iconostasis the boards or the bricks or the stones. In actuality, the iconostasis is a boundary between the visible and invisible worlds, and it functions as a boundary by being an obstacle to our seeing the altar, thereby making it accessible to our consciousness by means of its unified row of saints (i.e., by its cloud of witnesses) that surround the altar where God is, the sphere where heavenly glory dwells, thus proclaiming the Mystery. Iconostasis is vision. Iconostasis is manifestation of saints and angels- angelophania– a manifest appearance of heavenly witnesses that includes, first of all, the Mother of God and Christ Himself in the flesh, witnesses who proclaim that which is from the other side of mortal flesh. Iconostasis is the saints themselves. If everyone praying in a temple were wholly spiritualized, if everyone praying were truly to see, then there would be no iconostasis other than standing before God Himself, witnessing to Him by their holy countenances and proclaiming His terrifying glory by their sacred words.
But because our sight is weak and our prayers are feeble, the Church, in Her care for us, gave us visual strength for our spiritual brokenness: the heavenly visions on the iconostasis, vivid, precise, and illumined, that articulate, materially cohere, an image into fixed colors. But this spiritual prop, this material iconostasis, does not conceal from the believer (as someone in ignorant self-absorption might imagine) some sharp mystery; on the contrary, the iconostasis points out to the half-blind the Mysteries of the altar, opens for them an entrance into a world closed to them by their own struckness, cries into their deaf ears the voice of the Heavenly Kingdom, a voice made deafening to them by their having failed to take in the speech of ordinary voices. This heavenly cry is therefore stripped, of course, of all the subtly rich expressiveness of ordinary speech: but who commits the act of such stripping when it is we who fail to appreciate the heavenly cry because we failed first to recognize it in ordinary speech: what can be left except a deafening cry? Destroy the material iconostasis and the altar itself will, as such, wholly vanish from our consciousness as if covered over by an essentially impenetrable wall. But the material iconostasis does not, in itself, take the place of the living witnesses, existing instead of them; rather, it points toward them, concentrating the attention of those who pray upon them- a concentration speak figuratively, then, a temple without a material iconostasis opens windows in this wall, through whose glass we see (those of us who can see) what is permanently occurring beyond: the living witnesses to God. To destroy icons thus means to block up the windows; it means smearing the glass and weakening the spiritual light for those of us who otherwise could see it directly, who could (we could figuratively say) behold it in a transparent space free of earthly air, a space where we could learn to breathe the pure ethereal air and to live in the light of God’s glory: and when this happens, the material iconostasis will self-destruct in that vast obliteration which will destroy the whole image of this world- and which will even destroy faith and hope- and then we contemplate, in pure love, the immortal glory of God.