Ambrose of Milan
Catena Aurea · Lukasevangelium 9
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. And as he prayed, the fashion of his countenance was altered, and his raiment was white and glistering. And, behold, there talked with him two men, which were Moses and Elias: Who appeared in glory, and spake of his decease which he should accomplish at Jerusalem.
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.