Thank you for contacting BibleAsk.
Fulfillment: “And after six days Jesus taketh Peter, James, and John his brother, and bringeth them up into an high mountain apart, And was transfigured before them: and his face did shine as the sun, and his raiment was white as the light. And, behold, there appeared unto them Moses and Elias talking with him” (Matthew 17:1-3).
Matthew, Mark, and Luke record the narrative of the Transfiguration immediately following this prediction. 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, implying that the event was the fulfillment of the prediction.
The Transfiguration was a miniature demonstration of the kingdom of glory. Peter one of the disciples that were present at the Transfiguration also understood it like explained (2 Peter 1:16-18).
There is theological significance behind these two men being resurrected, and that is why they were chosen to attend to Jesus on the Mount of Transfiguration. The transfiguration represented the resurrection at the end of time. Moses represented those who will die and be resurrected and go to heaven, while Elijah represented those who will go to heaven without experiencing death.
Elijah was taken alive to Heaven: “And it came to pass, as they still went on, and talked, that, behold, there appeared a chariot of fire, and horses of fire, and parted them both asunder; and Elijah went up by a whirlwind into heaven” (2 kings 2:11), while, Moses received a private resurrection by Jesus (Michael): “Yet Michael the archangel, when contending with the devil he disputed about the body of Moses, durst not bring against him a railing accusation, but said, The Lord rebuke thee” (Jude 9). So, both Elijah and Moses were taken to heaven and did appear to Christ and some of the disciple at the transfiguration of Christ.
In His service,