Ante-Nicene Fathers, Vol IX:
Origen's Commentary on the Gospel of Matthew.: Chapter XLII

42.  The Meaning of the “Bright Cloud.”

Next to these come the words, “While He was yet speaking, behold, also, a bright cloud overshadowed them,” 5814 etc.  Now, I think that God, wishing to dissuade Peter from making three tabernacles, under which so far as it depended on his choice he was going to dwell, shows a tabernacle better, so to speak, and much more excellent, the cloud.  For since it is the function of a tabernacle p. 473 to overshadow him who is in it, and to shelter him, and the bright cloud overshadowed them, God made, as it were, a diviner tabernacle, inasmuch as it was bright, that it might be to them a pattern of the resurrection to come; for a bright cloud overshadows the just, who are at once protected and illuminated and shone upon by it.  But what might the bright cloud, which overshadows the just, be?  Is it, perhaps, the fatherly power, from which comes the voice of the Father bearing testimony to the Son as beloved and well-pleasing, and exhorting those who were under its shadow to hear Him and no other one?  But as He speaks of old, so also always does He speak through what He wills.  And perhaps, too, the Holy Spirit is the bright cloud which overshadows the just, and prophesies of the things of God, who works in it, and says, “This is My beloved Son in whom I am well-pleased;” but I would venture also to say that our Saviour is a bright cloud.  When, therefore, Peter said, “Let us make here three tabernacles,” 5815 …one from the Father Himself, and from the Son, and one from the Holy Spirit.  For a bright cloud of the Father, Son and Holy Spirit overshadows the genuine disciples of Jesus; or a cloud overshadows the Gospel and the law and the prophets, which is bright to him who is able to see the light of it in the Gospel, and the law, and the prophets.  But perhaps the voice from the cloud says to Moses and Elijah, “This is My beloved Son in whom I am well-pleased, hear Him,” as they were desirous to see the Son of man, and to hear Him, and to behold Him as He was in glory.  And perhaps it teaches the disciples that He who was, in a literal sense, the Son of God, and His beloved in whom He was well-pleased, whom it behoved them especially to hear, was He who was then beheld, and transfigured, and whose face shone as the sun, and who was clothed with garments white as the light.

Footnotes

Matt. xvii. 5.

The text is mutilated.