During a Bible discussion for seekers last week, one of them asked a question that led me to ponder this questions.
As I understand it, the body of Moses (not Elijah since he never died) should still have been in the grave at the time of the Transfiguration of Jesus--and would be pretty decomposed at that point. However, his spirit (and probably souls) would have been in Paradise at that time--still separated from his body until the resurrection at the last day.
And after six days Jesus took with him Peter and James, and John his brother, and led them up a high mountain by themselves. 2 And he was transfigured before them, and his face shone like the sun, and his clothes became white as light. 3 And behold, there appeared to them Moses and Elijah, talking with him. Matthew 17:1-3 ESV
If that is true, then what exactly did Peter, James and John see on the Mount of Transfiguration? Did they see the spirit of Moses? Can our spirits be seen with physical eyes? Were the disciples perhaps allowed to see spiritual things as Elisha appears to have done in 2 Kings 6?
When the servant of the man of God rose early in the morning and went out, behold, an army with horses and chariots was all around the city. And the servant said, “Alas, my master! What shall we do?” He said, “Do not be afraid, for those who are with us are more than those who are with them.” Then Elisha prayed and said, “O Lord, please open his eyes that he may see.” So the Lord opened the eyes of the young man, and he saw, and behold, the mountain was full of horses and chariots of fire all around Elisha. 2 Kings 6:15-17 ESV
As a side note, the rich man and Lazarus presumably "saw" each other as well.
I'm looking for the Protestant understanding of this.