Tradition is strong in the mind of man. And no other tradition prevails as strong as the supposition of the immortality of man's soul. However the Bible is very clear that the end of man is death--both in body and soul--then resurrection and then judgement.
The dead are dead. They are not alive in spirit form somewhere. They are dead in both body and soul See The Christian Hope. No matter how holy a person was in life when he dies, he is dead. Jesus Christ was the only man ever to be resurrected from the dead to everlasting glory. The others have to wait until the resurrections after Christ returns in judgement. This includes both Moses and Elijah.
When the dead appear to speak in the Bible it is either in allegory, parable, se'ance or a vision of the future.
A Parable is used In Luke 16:23, where the rich man cries from hades for relief, to illustrate the finality of judgement.
An Allegory is used in Revelation 6: 9-10 depicting the urgency for judgement as the righteous dead cry out for vengeance.
A Se'ance, by a witch, is used by King Saul to discover the future from devils impersonating the dead Samuel. l Samuel 28:7.
A Vision of the future occurred at the Mount of Transfiguration.
Other men such as Enoch and Elijah appear to have been "translated" directly to heaven, but if we examine the Bible closely we will see that Enoch--in his time-- was carried away by God protecting his life from the evil around him. In Elijah's case, at his death, he was carried up in the sky by a whirlwind--a sign accomplished for the sake of Elisha, Elija's servant. God hid Elijah's dead body in the same way He hid Moses's dead body. It could not be found by his disciples.
Other than these accounts, there is no indication that anyone other than the Lord Jesus Christ has ever ascended into heaven. That's what makes Jesus so special--he was dead and is now alive. He sits at the right hand of God Almighty and will eventually call his own to himself and raise the dead in judgement.
If any man deserved to ascend to heaven directly it would have been David--a man after God's own heart. But Peter denies this, saying that even though David testified of Christ's ascension, David himself had not ascended to heaven and his sepulcher was still around. Acts 2:34.
The devil works hard to make man believe that the dead don't really die. His forces are strong, especially impersonating the dead, through hauntings and se'ances, deceiving mankind into believing the old serpant's lie in Genesis, "Thou shall not surely die!"
The fourth way the dead appear to be alive in the Bible is in a Vision of the future. Many times throughout the Bible God communicates to his servants with events of the future and of heavenly events projected vividly into their minds. Paul, John, Enoch, Ezekial, Daniel had these visions. The disciples Peter, James and John also had a vision of the future as Peter recounts in his epistle:
2 Peter 1:16-18 For we have not followed cunningly devised fables, when we made known unto you the power and coming of our Lord Jesus Christ, but were eyewitnesses of his majesty. For he received from God the Father honor and glory, when there came such a voice to him from the excellent glory, This is my beloved Son, in whom I am well pleased. And this voice which came from heaven we heard, when we were with him in the holy mount [of transfiguration].
Peter saw a Future Vision of Jesus's power and coming in glory, even before Christ was crucified. He along with James and John were witnesses to a shared vision of the Son of man coming into his kingdom. With Christ, the righteous dead (such as Moses, Elijah and the saints) will be resurrected and rule with him in his kingdom. The vision of The Transfiguration included the resurrected Moses and Elijah who are dead now but will be made alive in the future.
That's why Moses and Elijah (who are dead) stood and talked to Jesus because in the future they will be made alive again and fellowship with their Lord. This is the nature of this vision!
The Transfiguration was not a se'ance. It did not bring Moses and Elijah out of the realm of the dead to speak to Jesus as the religious and spiritualist world claims.
In Matthew is the account (Mark's account is almost verbatim):
Mat 16:27-17:9 For the Son of man shall come in the glory of his Father with his angels; and then he shall reward every man according to his works. Verily I say unto you, There be some standing here, which shall not taste of death, till they see the Son of man coming in his kingdom. And after six days Jesus taketh Peter, James, and John his brother, and bringeth them up into a 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 Elijah talking with him. Then answered Peter, and said unto Jesus, Lord, it is good for us to be here: if thou wilt, let us make here three tabernacles; one for thee, and one for Moses, and one for Elijah. While he yet spake, behold, a bright cloud overshadowed them: and behold a voice out of the cloud, which said, This is my beloved Son, in whom I am well pleased; hear ye him. And when the disciples heard it, they fell on their face, and were sore afraid. And Jesus came and touched them, and said, Arise, and be not afraid. And when they had lifted up their eyes, they saw no man, save Jesus only. And as they came down from the mountain, Jesus charged them, saying, Tell the vision to no man, until the Son of man be risen again from the dead.
Additional information is given to us in Luke 9:30-31
And, behold, there talked with him two men, which were Moses and Elijah who appeared in glory, and spake of his decease which he should accomplish at Jerusalem.
In the above passage, Jesus teaches that he will come in the glory of God along with his angels (which also include his glorified saints, as later revealed in the scriptures). They will judge the earth. Jesus tells his disciples that some of them would actually see this occur--either in reality or in a vision. Jesus did not say they would live until the time of his return, he simply said that some would not taste of death before they saw him coming in to his kingdom. This would be realized 6 days and a few verses later in the Vision of the Transfiguration.
Six days after making this prophecy, Jesus takes Peter, James and John to a high mountain away from everything. Then the vision occurs. At the beginning of the vision, the disciples see Jesus's face change and shine as the sun. His clothes became as white as the light. This agrees with the depiction of the angel representing Christ in Revelation 1:16:
And he had in his right hand seven stars: and out of his mouth went a sharp two-edged sword and his countenance was as the sun shineth in his strength.
Then a vision of the future-resurrected Moses and Elijah appeared talking to the glorified Christ. This vision of the future kingdom had Jesus talking with those important men concerning his death in Jerusalem. Peter, totally befuddled by the vision, offered to construct tents for Jesus, Moses and Elijah assuming they would be staying for a while and would need some shelter. This vision was so real to Peter that he felt he needed to get involved. Then God dramatically tells the disciples to listen to His beloved Son. They fall down in fear. The vision disappears leaving only Jesus to comfort them.
Visions and the hope of God's coming kingdom are all that keep saints going at times when things get rough. Jesus knew his inner circle needed to witness first hand the reality of his kingdom. They needed the hope of this righteous kingdom prominent in their hearts to help them continue as did Abraham, and as do all believers. See Hebrews 11:10:
For he looked for a city which hath foundations, whose builder and maker is God.
Paul was given visions concerning the kingdom of God, these gave him special strength to continue to the end
2Co 12:1-4It is not expedient for me doubtless to glory. I will come to visions and revelations of the Lord. I knew a man [speaking of Paul, himself] in Christ above fourteen years ago, (whether in the body, I cannot tell; or whether out of the body, I cannot tell: God knoweth; [the vision was so real to Paul he couldn't tell if God transported him physically or just mentally to the future]) such a one caught up to the third heaven [the future Paradise will be the third heaven and earth]. And I knew such a man, (whether in the body, or out of the body, I cannot tell: God knoweth;) How that he was caught up into paradise, and heard unspeakable words, which it is not lawful for a man to utter.
In John 8:55-56, Jesus tells his enemies that Abraham in a vision saw Christ's Kingdom and was glad.
Yet ye have not known him; but I know him: and if I should say, I know him not, I shall be a liar like unto you: but I know him, and keep his saying. Your father Abraham rejoiced to see my day: and he saw it, and was glad.
The apostle John, after his experience with Peter and James, once again saw a vision of Christ in his kingdom, also known as the Lord's Day. This is the basis for Revelations:
Rev 1:9I John, who also am your brother, and companion in tribulation, and in the kingdom and patience of Jesus Christ, was in the isle that is called Patmos, for the word of God, and for the testimony of Jesus Christ. I was in the Spirit on the Lord's day [the day of the Lord's judgement], and heard behind me a great voice, as of a trumpet,
Daniel also had visions about the Lord's kingdom:
Dan 8:16-17 And I heard a man's voice between the banks of Ulai, which called, and said, Gabriel, make this man to understand the vision. So he came near where I stood: and when he came, I was afraid, and fell upon my face: but he said unto me, Understand, O son of man: for at the time of the end shall be the vision.
Zec 4:1-3And the angel that talked with me came again, and waked me, as a man that is wakened out of his sleep, And said unto me, What seest thou? And I said, I have looked, and behold a candlestick all of gold, with a bowl upon the top of it, and his seven lamps thereon, and seven pipes to the seven lamps, which are upon the top thereof: And two olive trees by it, one upon the right side of the bowl, and the other upon the left side thereof.
(The two olive trees; men who play a prominent role in the second coming of Christ, akin to John the Baptist before his first coming)
Eze 37:1The hand of the LORD was upon me, and carried me out in the spirit of the LORD, and set me down in the midst of the valley which was full of bones, Eze 37:8 And when I beheld, lo, the sinews and the flesh came up upon them, and the skin covered them above: but there was no breath in them. Eze 37:12 Therefore prophesy and say unto them, Thus saith the Lord GOD; Behold, O my people, I will open your graves, and cause you to come up out of your graves, and bring you into the land of Israel.
This is a vision of the resurrection.
The Mount of Transfiguration was a glorious example of God's ability to communicate to his people with visions of the future, it was not a se'ance where the dead were called forth from their realm to speak with the living. Tradition once again leads people astray and leads God's people away from the glorious truths wihin His Word.
The dead are dead and will stay dead until the resurrection of the dead.
but there are unholy transfigurations when devils, pretending to be the dead, attempt to communicate explicitly with their victims.
Unbiblical, unholy se'ances and transfigurations (practiced by mediums). Deadly Strange Fires. Flee from this vexation! The Dead are dead and will stay dead until the resurrections. If you hear from the dead you are hearing from vulgar devils!
Saul broke the commandment in Leviticus to stay away from people who claimed to speak with the dead-- Necromancers,Mediums and Witches. It was common knowledge that those ungodly people were possessed with demons and they were speaking for Satan just as street-corner mediums, palm readers and fortune tellers do today.
Lev 20:6And the soul that turneth after such as have familiar spirits and after wizards, to go a whoring after them, I will even set my face against that soul, and will cut him off from among his people.
Deu 18:10-12There shall not be found among you any one that maketh his son or his daughter to pass through the fire, or that useth divination, or an observer of times, or an enchanter, or a witch, Or a charmer, or a consulter with familiar spirits or a wizard, or a necromancer. For all that do these things are an abomination unto the LORD: and because of these abominations the LORD thy God doth drive them out from before thee.
1 Samuel 28:6-30
And when Saul enquired of the LORD, the LORD answered him not, neither by dreams, nor by Urim, nor by prophets.
Then said Saul unto his servants, Seek me a woman that hath a familiar spirit, that I may go to her, and enquire of her. And his servants said to him, Behold, there is a woman that hath a familiar spirit at Endor.
And Saul disguised himself, and put on other raiment, and he went, and two men with him, and they came to the woman by night: and he said, I pray thee, divine unto me by the familiar spirit, and bring me him up, whom I shall name unto thee.
And the woman said unto him, Behold, thou knowest what Saul hath done, how he hath cut off those that have familiar spirits, and the wizards, out of the land: wherefore then layest thou a snare for my life, to cause me to die?
And Saul sware to her by the LORD, saying, As the LORD liveth, there shall no punishment happen to thee for this thing.
Then said the woman, Whom shall I bring up unto thee? And he said, Bring me up Samuel.
And when the woman saw Samuel, she cried with a loud voice: and the woman spake to Saul, saying, Why hast thou deceived me? for thou art Saul.
And the king said unto her, Be not afraid: for what sawest thou? And the woman said unto Saul, I saw gods ascending out of the earth.
And he said unto her, What form is he of? And she said, An old man cometh up; and he is covered with a mantle. And Saul perceived [was deceived] that it was Samuel [a familiar spirit], and he stooped with his face to the ground, and bowed himself.
And Samuel [a familiar spirit] said to Saul, Why hast thou disquieted me, to bring me up? And Saul answered, I am sore distressed; for the Philistines make war against me, and God is departed from me, and answereth me no more, neither by prophets, nor by dreams: therefore I have called thee, that thou mayest make known unto me what I shall do.
Then said Samuel, Wherefore then dost thou ask of me, seeing the LORD is departed from thee, and is become thine enemy?
And the LORD hath done to him, as he spake by me: for the LORD hath rent the kingdom out of thine hand, and given it to thy neighbour, even to David:
Because thou obeyedst not the voice of the LORD, nor executedst his fierce wrath upon Amalek, therefore hath the LORD done this thing unto thee this day.
Moreover the LORD will also deliver Israel with thee into the hand of the Philistines: and to morrow shalt thou and thy sons be with me: the LORD also shall deliver the host of Israel into the hand of the Philistines.
Then Saul fell straightway all along on the earth, and was sore afraid, because of the words of Samuel: and there was no strength in him; for he had eaten no bread all the day, nor all the night.
And the woman came unto Saul, and saw that he was sore troubled, and said unto him, Behold, thine handmaid hath obeyed thy voice, and I have put my life in my hand, and have hearkened unto thy words which thou spakest unto me.
The Hebrew word for familiar spirit is OB (pronounced obe) the hollow sound coming from an empty bottle. The Hebrews likened these witches to empty leather bottles that echoed the hollow sounds of evil spirits pretending to be the speaking dead. Saul's witch was possessed with a devil who was intimately familiar with Samuel. The devil easily deceived Saul, sealing his doom.
Familiar Spirits, who possess these empty human bottles (witches, mediums and necromancers), were so termed by those in the Middle English and King James period. They were prominently depicted and described in the writings of Shakespeare and personified in characters such as Puck in A Midsummer's Night Dream. Shakespeare's culture called them fairies or sprites and gave them a romantic appeal; however, they were (and are presently) actually harmful and dangerous demons intimately familiar with the lives of people, seeking to decieve and harm them artfully and subtly. They are no less than demon servants of Lucifer. Because these devils are intimately familiar with the deceased they can easily pretend to be the deceased in a se'ance, just as the demon who pretended to be Samuel easily deceived Saul.
A warning to Christians. Never visit a fortune teller, palm reader, se'ance, tarot card reader etc etc etc. These will all open doors to evil spirits that are not easily parted with. Beware! Worship God only and forsake other forms of inquiry.
In conclusion Peter, James and John and Jesus, were not witnessing the dead Moses and Elijah visiting Jesus from the spiritual realms. They were actually having a vision from God of Jesus's power and glory in his future kingdom. They were witnessing a future conversation Jesus would be having with Moses and Elijah. This was done not only to give Jesus vision and strength but also to inspire the disciples helping them through the unimaginable events they would soon experience.