Listen... in Matthew 17:9 about Moses and Elijah...appeared and spoke with Jesus Christ at the Mount of Transfiguration. Peter, James and John saw them. What were their bodies like? Was it "temporary" before Christ went to the Cross? Or are you going to deny this altogether by saying it's just a supernatural "vision" rather than real physical events and conclude that Moses and Elijah were not truly there, perhaps, because they were not supposed to have bodies or be alive at that time before the Cross?
This is a vision, but it is important to note that these two Old Covenant faithful saints were shown in the vision as proof there is life (spiritual) after death for those of Old who died before the advent of Christ. According to the Old Covenant prophets those of faith would be redeemed from the grave after the promised Messiah/Savior comes. That's why Christ tells them not to tell anyone of the vision until the Son of man has risen from the grave. If the Old Covenant saints were not spiritually alive after death, as shown through the parable of Lazarus and the rich man, then the vision would not have shown these two spiritually alive, not physically alive. It was in knowing the spirit is still alive of those of Old who died in faith, that would help the disciples to believe that John the Baptist had come in the spirit and power of Elijah, just as the prophets of Old and Christ say he would. Of course, giving greater confirmation that Christ, The Messiah/Savior was the Son of God, called by the name of Jesus.
Matthew 17:10-12 (KJV) And his disciples asked him, saying, Why then say the scribes that Elias must first come? And Jesus answered and said unto them, Elias truly shall first come, and restore all things. But I say unto you, That Elias is come already, and they knew him not, but have done unto him whatsoever they listed. Likewise shall also the Son of man suffer of them.
Malachi 4:5-6 (KJV) Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the LORD: And he shall turn the heart of the fathers to the children, and the heart of the children to their fathers, lest I come and smite the earth with a curse.