It is significant that Matthew, Mark, and Luke record the Transfiguration immediately following this prediction found in Mark 9:1. There is no break in the narrative; no chapter or verse division in the Greek original; and furthermore all three mention the fact that the Transfiguration occurred about a week after this statement. All this means that the event was the fulfillment of the prediction.
The connection between the two sections of narrative seems to rule out the possibility that Jesus here pointed to anything but the Transfiguration, which was a miniature illustration of the kingdom of glory. clearly, Peter understood this to be the case as you can read in 2 Peter 1:16-18.
The people living to see a miniature example of the kingdom of God coming were Peter, James, and John. The disciples acknowledged the heavenly visitants either from their conversation or by divine inspiration. Moses was the great deliverer and lawgiver of the Hebrews, and Elijah the one who saved it in a time of great idolatry and sin. Here were living representatives to testify to the divinity of Jesus, even as “Moses and all the prophets,” through their books, had testified of Him (Luke 24:44).
It is important to note that regarding both Elijah and Moses, the Scriptures record the fact that the Elijah was translated to heaven without seeing death (2 Kings 2:11, 12) and Moses raised from the dead (Judge 9). The fact that Moses and Elijah appeared with Christ at this time is therefore not to be taken to prove that all the righteous dead are in heaven.
A Type for the Second Coming
Moses and Elijah, one raised from the dead and the other translated without seeing death, appeared with Jesus, as a type of the glorious kingdom in which the saints throughout history will be with Christ coming (Matthew 25:31; Colossians 3:4; 1 Thessalonians 4:16, 17). This was a miniature example of how Jesus’ second coming would be like and these three disciples got to see it and hence they fulfilled the prediction “that some that stand here shall not taste death till they have seen the kingdom of God come.”
In His service,