St Cyril explains that in saying that there were some who would not not taste death until they had seen ‘the kingdom of God’, Jesus was referring to the sight of the glory in which he would appear at his second coming – and now those who had been there when he said it saw the promise fulfilled on Mt Tabor. The Holy Law of Moses and the teachings of the Prophets foreshadowed the mysteries of Christ, and he has them as his bodyguard – these are further testimony that he is Lord of all.
St Ambrose points out the same fact, that it was the disciples who had been told by Jesus that they should not taste death until they had seen his glory, who now see that glory. We cannot tell why these three were chosen, but we do know they had especial graces: Peter was entrusted with the Keys; John with the Blessed Virgin, and James was the first to mount a bishop’s throne. The transfiguration shows clearly who Christ is and foreshadows his coming again in glory.
Bede notes that Luke writes most fully on the Transfiguration. It is he who records that Moses and Elijah appeared in majesty, and that they spoke with Jesus about what was about to be fulfilled in Jerusalem, as well as of his resurrection – they represent the Law and the Prophets that were fulfilled in Christ. Peter is the type of sinful man when, sleepy and lacking in vigilance he almost misses the sight of the Lord in glory, but he is also, as usual, our model in that he wakes and, as we will when we do, he sees that glory.It is typical of Peter that his zeal outstrips his knowledge, but his fault here is on the side of piety. Peter does not yet understand that it is only by undergoing death in the flesh that death can be abolished by the resurrection.
Ambrose tells us that the cloud is the overshadowing of the Holy Spirit who will reveal all the secrets at the last – here the voice of God tells those present who Jesus is. Bede adds that the voice of God does not forbid them to listen to the Law (Moses) or the Prophets (Elijah), but does make plain that the Son takes precedence – the Law and the Prophets have to be read through him.
St Gregory Nazianzus wrote:
He was bright as the lightning on the mountain and became more luminous than the sun, initiating us into the mystery of the future.
Ephrem the Syrian tells us that Jesus commanded them not to speak of what had passed because he knew others would not believe – as none would until he died and rose again – as he would soon.