The following Greek commentaries are from the Ancient Christian Texts series, Greek Commentaries on Revelation, William C. Weinrich trans.
Oecumenius (6th or 7th Century), Commentary on the Apocalypse, Sixth Discourse (pp. 51-53)
"And the temple of God in heaven was opened," it says, "and the ark of his covenant was seen in his temple." When this had been said, those good things that had been hidden, and in addition to these certain new mysteries, were seen by the saints. For this is the signification of the ark of the covenant being opened. And Paul shows that the good things of the coming age are hidden from people at the present time by saying, "What no eye has seen, nor ear heard, nor the heart of man conceived, that God has prepared for those who love him." And that there will be certain mysteries and another knowledge that is now unknown, the Lord shows when he said, "I shall not drink again of this fruit of the vine until that day when I drink it new with you in my Father's kingdom."
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The vision intends to describe more completely to us the circumstances concerning the anti-christ, whom we mentioned briefly in previous discussion. However, since the incarnation of the Lord, which made the world his possession and subjected it, provided a pretext for Satan to raise up the antichrist and to choose him as his instrument--for the antichrist will be raised to cause the world again to fall from Christ and to persuade it to desert to Satan--and since moreover his fleshly conception and birth was the beginning of the incarnation of the Lord, the vision gives a certain order and sequence to the material that it is going to discuss and begins the discussion from the fleshly conception of the Lord by portraying for us the mother of God [lit. Theotokos]. What does he say? "And a sign appeared in heaven, a woman clothed with the sun, and the moon under her feet." As I said, it is speaking about the mother of our Saviour. And the vision appropriately depicts her as in heaven and not on the earth, for she is pure in soul and body, equal to angel and a citizen of heaven. She possesses God who rests in heaven-- "for heaven is my throne," it says -- yet she is flesh, although she has nothing in common with the earth, nor is there any evil in her. Rather, she is fully exalted, wholly worthy of heaven, even though she possesses our own human nature and substance. For the Virgin is consubstantial with us. Let the impious teaching of Eutyches, which makes the fanciful claim that the Virgin is of another substance than we, be excluded from the belief of the holy courts together with his other opinions.
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"And she was with child," it says, "and she cried out in her pangs of birth, in anguish for delivery." Clearly Isaiah speaks concerning her: "Before she was in labor she gave birth; before the pain of her labor she fled and gave birth to a son." Also in his thirteenth homily on the Song concerning the Lord, Gregory says, "whose pregnancy remains without union, and the childbirth without defilement, and the labor free of pain." If according to the prophet and to such a teacher of the church the Virgin escaped the pain of childbirth, how is it that here it says "she cried out in her pangs of birth, in anguish for delivery"? What is said is not contradictory. By no means! For there would be nothing contradictory said by the same Spirit who was speaking through both. Rather, you will understand the present phrase "she cried out and was in anguish" in this way. Until the holy angel said to Joseph that that which was borne in her womb was of the Holy Spirit, she was faint of heart, as is natural for a virgin, and she blushed before her betrothed and thought that perhaps from the secrecy of the marriage he might think that she was in labor. And so, according to the rules of figurative language, he calls this faintheartedness and sorrow a "crying out" and "anguish." Nor is this unusual, for even to the blessed Moses, when he was spiritually conversing with God and losing heart--for he saw Israel in the desert surrounded by the sea and the enemy--God said, "Why are you crying to me?" So also here, the vision calls the troubled disposition of the Virgin in her mind and heart a crying out. But may you, who by your unspeakable birth did bring to an end the faintheartedness of our undefiled servant, your mother according to the flesh, but my mistress, the holy mother of God, also forgive my sins. For it is proper to give you glory forever. Amen.
Andrew aka Andreas of Caesarea (d. 637) Commentary on the Apocalypse, Book Eleven, Chapter 33 (pp. 154-55)
Concerning the persecutions of the church, both those formerly and those under the antichrist
[11:19] And the temple of God in heaven was opened, and the ark of his covenant was seen within his temple; and there were flashes of lightning, voices, peals of thunder, and earthquake and heavy hail.
By the opening of the heaven and the vision of the ark is shown the revelation of those blessings that have been prepared for the saints. According to the apostle, these blessings are hidden in Christ in whom the fullness of deity dwells bodily. And these things will be revealed when the punishments of the lawless and impious like terrifying voices and lightnings and thunder and hail. The earthquake signifies the transposition of present things.
[12:1] And a great sign appeared in heaven, a woman clothed with sun, with the moon under her feet, and on her head a crown of twelve stars.
Some believe that the woman refers generally to the mother of God who suffered that which was soon to happen before her bearing of God was known. However, the great Methodius understands her to be the holy church, believing that what is narrated concerning her is unsuited of the divine birth since the Lord had been born already a long time previously. It is well to recall these words of the blessed Methodius who in his Symposium says in the person of the virgin Procles: "The woman clothed with the sun is the church. Instead of such clothing as we have, she has light. She uses stars as we do gold and brilliant stones; however, her stars are better and brighter than those on earth." And afterward Methodius continues: "She stands on the moon. I think that the moon symbolically refers to the faith of those who have been purified from corruption by the laver, for very moist substance is dependent on the moon. Laboring and giving birth to natural persons as spiritual persons, the church forms them according to the likeness and the form of Christ." And later he says, "It is not necessary to think that it is Christ who is the one born. For long before the Apocalypse, the mystery of the incarnation of the Word was fulfilled. But John speaks concerning things present and things to come." And a little later he writes, "So it is necessary to confess that the church is she who labors and gives birth to those who are baptized. As the Spirit says in Isaiah: 'Before she who travails brought forth; she fled and brough forth a male child.' From whom did she flee? Surely from the dragon, that the spiritual Zion might give birth to a masculine people." And a little later: "So that in each one Christ is born spiritually. And for this reason the church swells and labors until Christ who is born be formed in us, so that each one, partaking in Christ, might become Christ." Therefore, the church is clothed with sun of righteousness. She hold under her feet both the light of the Law, which, as does the moon, gives light at night and the life of the world which, as the moon, is changing. On her head she wears the crown of the apostolic teachings and of the virtues. The author teaches that just as moist substances are dependent on the moon, so the figure of the moon signifies baptism. Here baptism is figuratively called the sea, which is salvation to those who have been born anew but is destruction to the demons.
