This question came from "Ask the Pastor". The transfiguration scene from Matthew 17:1, a couple of questions:
How did Peter, James, and John recognize that it was Moses and Elijah that appeared before them? I'm quite certain they never met but perhaps God opened their eyes and revealed it to them?
What was the purpose of the transfiguration? Was it to give Peter, James, and John a taste of what heaven would be like? Was it to meant to commission them as God spoke saying "This is my Son, whom I love, with him I am well pleased. Listen to him" Please explain.
Well, of course there was no way to know who these two apparitions were unless there was something in their dress or they were carrying some clue. For instance, the white bearded figure with the two tablets or the camel hair outfit on Elijah (see John the Baptist description). I assume that to be the case, that there was some clue in the manner of presentation. The purpose of the transfiguration was to demonstrate that the prophets (represented by Elijah) and the Law (represented by Moses) bear testimony to Jesus. This was a great revelation to the three in the inner circle of the disciples. Two of those three wrote in the New Testament (as opposed to,say, Bartholomew or Thaddeus), the other was the first martyr. So it would be important revelation to the writers of the NT and the first martyr of the Apostles (Acts 12.1). All of them clearly got the message as is witnessed by quotations from the OT Law and prophets in their books and one needs to only look at the speech of Stephen in Acts 7to see how this all plays into the attempts to reach the first century Jewish audience by quoting from their scriptures.
There doesn't seem to be anything here that is intended to relate what heaven is like. The purpose is revelation of Jesus. Peter actually quotes this moment (2 Peter 2.16ff) so we see it's intent is christology not eschatology. Without a clear, accurate, and articulate vision of Christ we cannot attempt to bear witness to Him. May God give us the revelation of the Son!