Luke 9:30

After that, Pentecost is a most joyous space for conferring baptisms; wherein, too, the resurrection of the Lord was repeatedly proved among the disciples, and the hope of the advent of the Lord indirectly pointed to, in that, at that time, when He had been received back into the heavens, the angels told the apostles that "He would so come, as He had withal ascended into the heavens; " at Pentecost, of course.

Our Lord, when He made known to His disciples the great mystery of His second coming, that it might not seem that they were to believe in His words only, proceeds to works, manifesting to them, through the eyes of their faith, the image of His kingdom; as it follows, And it came to pass about an eight days after these sayings, he took Peter and John and James, and went up into a mountain to pray.

Moses and Elijah appeared beside him so that they might know that he was Lord of the prophets. He transformed his face on the mountain before he died, so that they would not be in doubt concerning the transformation of his face after his death. He changed the garments which he was wearing so that they might know that it is also he who will raise to life the body with which he was clothed. He, who gave his body a glory that no one can reach, is able to raise it to life from the death that everyone tastes.

For Moses himself, who was at once the lawgiver, and the high priest, and the prophet, and the king, and Elijah, the zealous follower of the prophets, were present at our Lord's transfiguration in the mountain,

What strange thing do we announce when we say that God became man and when you say that Abraham received the Lord as a guest? What strange thing do we announce when Jacob says, “I have seen a heavenly being face to face, yet my life has been spared”? The same Lord who ate with Abraham also ate with us. What strange thing do we announce? We present two witnesses who stood before the Lord on Mount Sinai: Moses was “in the hollow of the rock,” and Elijah was once in the hollow of the rock. Being present at his transfiguration on Mount Tabor, they spoke to his disciples “of his death that he was about to fulfill in Jerusalem.”

If then we also wish not to fear death, let us stand where Christ is. For they only cannot taste death who are able to stand with Christ, wherein we may consider from the nature of the very word, that they will not experience even the slightest perception of death, who are thought worthy to obtain union with Christ. At least let us suppose that the death of the body is tasted by touch, the life of the soul preserved by possession; for here not the death of the body, but of the soul, is denied.

Or, Peter went up, who received the keys of the kingdom of heaven; John, to whom was committed our Lord's mother; James, who first suffered martyrdom. (Acts 12:1.)

Now in a mystical manner, after the words above said, is exhibited the transfiguration of Christ, since he who hears the words of Christ, and believes, shall see the glory of His resurrection. For, on the eighth day the resurrection took place. Hence also several Psalms are written, 'for the eighth,' (pro octava.) or perhaps it was that He might make manifest what He had said, that he who for the word of God shall lose his own life, shall save it, seeing that He will make good His promises at the resurrection.

But Matthew and Mark have related that He took them with Him after six days, of which we may say after 6000 years, (for a thousand years in the Lord's sight are as one day;) but more than 6000 years are reckoned. We had rather then take the six days symbolically, that in six days the works of the world were completed, that by the time we may understand the works, by the works the world. And so the times of the world being finished, the resurrection to come is declared; or because, He who has ascended above the world, and has passed beyond the moments of this life, is waiting, seated as it were on a high place, for the everlasting fruit of the resurrection.

I should think that in the three who are taken up into the mountain, was contained in a mystery the human race, because from the three sons of Noah sprung the whole race of man; I did not perceive that they were chosen out. Three then are chosen to ascend the mountain, because none can see the glory of the resurrection, but they who have preserved the mystery of the Trinity with inviolable purity of faith.

Or else, according to your capacity is the word either lessened or increased to you, and unless you ascend the summit of a higher wisdom, you behold not what glory there is in the word of God. Now the garments of the Word, are the discourses of the Scriptures, and certain clothings of the Divine mind; and as His raiment shone white, so in the eyes of your understanding, the sense of the divine words becomes clear. Hence after Moses, Elias; that is, the Law and the Prophets in the Word. For neither can the Law exist without the Word, nor the Prophet, unless he prophesied of the Son of God.

(Hom. 56. in Matt.) Or else this took place because the multitude said He was Elias or Jeremias, to show the distinction between our Lord and His servants. And to make it plain that He was not an enemy of God, and transgressor of the law, He showed these two standing by Him; (for else, Moses the lawgiver, and Elias who was zealous for the glory of God, had not stood by Him,) but also to give testimony to the virtues of the men. For each had ofttimes exposed Himself to death in keeping the divine commands. He wishes also His disciples to imitate them in the government of the people, that they might be indeed meek like Moses, and zealous like Elias. He introduces them also to set forth the glory of His cross, to console Peter and the others who feared His Passion. Hence it follows, And spake of his decease, which he should accomplish at Jerusalem.

Besides, Moses and Elijah stood at Jesus' side and spoke with one another about his departure that he was about, it says, to accomplish at Jerusalem. This meant the mystery of the dispensation in the flesh and of his precious suffering upon the cross. It is also true that the law of Moses and the word of the holy prophets foreshadowed the mystery of Christ. The law of Moses foreshadowed it by types and shadows, painting it as in a picture. The holy prophets in different ways declared beforehand that in due time he would appear in our likeness and for the salvation and life of us all, agree to suffer death on the tree. Moses and Elijah standing before him and talking with one another was a sort of representation. It excellently displayed our Lord Jesus Christ as having the law and the prophets for his bodyguard. It displayed Christ as being the Lord of the Law and the Prophets, as foretold in them by those things that they proclaimed in mutual agreement beforehand. The words of the prophets are not different from the teachings of the law. I imagine this was what the most priestly Moses and the most distinguished of the prophets Elijah were talking about with one another.

The mystery, namely, of His incarnation, also the life-giving Passion accomplished on the sacred cross.

And behold, two men were speaking with him. They were Moses and Elias, of whom we read that one died, and the other was taken up into heaven. Unless this signifies the future glory of all the saints with the Lord in majesty, who at the time of judgment will reign with him, either found alive in the flesh or resurrected from death tasted long ago. For as the Apostle testifies, "The dead who are in Christ will rise first, then we who are alive, who are left, will be caught up together with them in the clouds to meet the Lord in the air, and so we shall always be with the Lord" (1 Thess. IV). Alternatively, Moses and Elias, that is, the lawgiver and the greatest of the prophets, appear and speak with the Lord to show that he is the one whom all the writings of the law and the prophets foretold. They appear, however, not in the lowlands, but on the mountain with him, because only those who seek the divine heights with their minds will perceive the majesty of the holy Scripture fulfilled in the Lord. Consequently, even the Jews saw Moses, but they did not merit to follow him as he ascended to God on the mountain. They see him also when he returned, but not without a veil. They knew Elias, but only Elisha with the sons of the prophets beheld the triumph of his ascent, because many of us read the words of Scripture here and there, but very few understand how lofty it shines in the mysteries of Christ.

For as He rose from the dead after the seventh day of the Sabbath, during which He lay in the tomb, we also after the six ages of this world, and the seventh of the rest of souls, which meanwhile is passed in another life, shall rise again as it were in the eighth age.

Hence He ascends the mountain to pray and be transfigured, to show that those who expect the fruit of the resurrection, and desire to see the King in His glory, ought to have the dwelling place of their hearts on high, and be ever on their knees in prayer.

Now the transfigured Saviour shows the glory of His own coming, or our resurrection; who as He then appeared to His Apostles shall in like manner appear to all the elect. But the raiment of the Lord is taken for the band of His Saints, which in truth when our Lord was upon earth seemed to be despised, but when He sought the mount, shines with a new whiteness; for now are we the sons of God; and it does not yet appear what we shall be. But we know that, when he shall appear, we shall be like him. (1 John 3:2.)

Luke writes more clearly of how they appeared and what they spoke about with him. Luke says that Moses and Elijah were seen in majesty, and they spoke of his passing away which he was about to fulfill in Jerusalem. Moses and Elijah, who talked with the Lord on the mountain and spoke about his passion and resurrection, represent the revelations of the law and prophets that were fulfilled in the Lord.…It is appropriate that the Evangelist reported Moses and Elijah were “seen in majesty.” The mark of the favor with which they are to be crowned is shown by the preeminence of their majesty. It is also appropriately recorded that they spoke about his passing away, which was to be fulfilled in Jerusalem. To his faithful, the Redeemer’s passion has become a unique subject for praise. The more they remember that they could not have been saved apart from his grace, the more they should always ponder the greater memory of this grace in a faithful heart, and bear faithful witness to it.

(Orat. de Trans fig. §. 8.) Matthew and Mark indeed say that the transfiguration took place on the sixth day after the promise made to the disciples, but Luke on the eighth. But there is no disagreement in these testimonies, but they who make the number six, taking off a day at each end, that is, the first and the last, the day on which He makes the promise, and that on which He fulfilled it, have reckoned only the intervening ones, but He who makes the number eight, has counted in each of the two days above mentioned. But why were not all called, but only some, to behold the sight? There was only one indeed who was unworthy to see the divinity, namely Judas, according to the word of Isaiah, Let the wicked be taken away, that he should not behold the glory of God. (Isai. 26:10 LXX.) If then he alone had been sent away, he might have, as it were from envy, been provoked to greater wickedness. Henceforward He takes away from the traitor every pretext for his treachery, seeing that He left below the rest of the company of the Apostles. But He took with Him three, that in the mouths of two or three witnesses every word should be established. He took Peter, indeed, because He wished to show him that the witness he had borne to Him was confirmed by the witness of the Father, and that he was as it were to preside over the whole Church. He took with Him James, who was to be the first of all the disciples to die for Christ; but He took John as the clearest singer of the sacred doctrine, that having seen the glory of the Son, which submits not to time, he might sound forth, In the beginning was the Word. (John 1:1.)

(ut sup. 10.) Servants however pray in one way; our Lord prayed in another. For the prayer of the servant is offered up by the lifting up of the mind to God, but the holy mind of Christ, (who was hypostatically [ὑπόστασιν] united to God,) prayed, that He might lead us by the hand to the ascent, whereby we mount up in prayer to God, and teach us that He is not opposed to God, but reverences the Father as His beginning; (ὡς ἀρχὴν ἑαυτὸν) nay, even tempting the tyrant, who sought from Him whether He were God, (which the power of His miracles declared,) He concealed as it were under the bait a hook; that he who had deceived man with the hope of divinity might fitly himself be caught with the clothing of humanity. Prayer is the revelation of Divine glory; as it follows, And as he prayed, the fashion of his countenance was altered.

(ut sup. 13.) Now the devil, seeing His face shining in prayer, recollected Moses, whose face was glorified. But Moses indeed was arrayed with a glory, which came from without; our Lord, with that which proceeded from the inherent brightness of Divine glory. (Exod. 34:29.) For since in the hypostatical union there is one and the same glory of the Word and the flesh, He is transfigured not as receiving what He was not, but manifesting to His disciples, what He was. Hence, according to Matthew, it is said, that He was transfigured before them, and that His face shone as the sun; (Mat. 17:2.) for what the sun is in things of sense, God is in spiritual things. And as the sun, which is the fountain of light, cannot be easily seen, but its light is perceived from that which reaches the earth; so the countenance of Christ shines more intensely, like the sun, but His raiment is white as snow; as it follows, And his raiment was white and glistering; that is, lighted up by its participation of the divine light. And a little afterwards, But while these things were so, that it might be shown there was but one Lord of the new and old covenant, and the mouths of heretics might be shut, and men might believe on the resurrection, and He also, who was transfigured, be believed to be the Lord of the living and the dead, Moses and Elias, as servants, stand by their Lord in His glory; hence it follows, And behold there talked with him two men. For it became men, seeing the glory and confidence of their fellow servants, to admire indeed the merciful condescension of the Lord, but to emulate those who had laboured before them, and looking to the pleasantness of future blessings, to be the more strengthened for conflicts. For he who has known the reward of his labours, will the more easily endure them.

Or, He takes these with Him as men who were able to conceal this thing, and reveal it to no one else. But going up into a mountain to pray, He teaches us to pray solitary, and going up, into stooping to earthly things.

The Transfiguration and the walking on the water are glimpses of the beauty and the effortless power over all matter which will belong to men when they are really waked by God.