Thanks to Gary Kreme.
When Jesus told Nicodemas, "You must be born again," most scholars believe that he was speaking allegorically. To be "born again" is to embrace a new identity.
During the final aspects of her Godly life, the Christian becomes a "mystic." This is a person who realizes that her little mind is actually a part of a much vaster, more immense Mind-- the Mind of God. She then realizes that God is not like the old primitive Jehovah-- that God does not live above the clouds or in a mountain such as Sinai, but lives as the "indwelling Holy Spirit of Love" within her heart.
Mystics, in their writings, call the earthly identity the "ego." This is the name on your birth-certificate and/or driver's license. But, deep within your mind, you are so much more. Jesus came to, among other reasons, show us the Love of a fully enlightened (realized) human being. For he said that he would go forward into death, and then return, demonstrating that death was not the "end," but a phase along the great Way.
He said, The Father and I are one." (Jn. 10:30) But we have no other verses where he said that these words applied to only him. Mystics from all over the world, from every culture and century, believe that, like Jesus, they are also a part of the One, the Mind, Good, which is "truth" or "reality."
God is the vast, immense Mind that dwells at the very Center of all minds, and so, She is aware of whatever passes through any and all minds.
The material universe is a projection, dream, or virtual reality projected by this Mind. Therefore, nothing in the "material" world is absolutely "real." This is indicated by how material things always change, or fall apart (returning to dust), or both.
Only Mind is real. This means that all sentient (selfaware) beings are also real, and sacred. Your sisters, brothers, mother, father, and other relatives, pets, animals, and friends are sacred (holy) because they also are part of the One. So, for that matter, are dogs, cats, horses, and a wide spectrum of other creatures. This is why a truly enlightened person always stands up for animal rights and against barbarity and cruelty.
A "person" who knows that she is part of the One, the Mind, is no longer the same "person." (This word comes from the Latin persona, and means "mask.") So, we must ask, "Who is wearing the mask?"
It is your Soul, that part of your mind that existed before this life, and will continue to exist when this life is over. That Soul arises from the beautiful Love-mind, Godmind, or God.
When you realize this very deeply, you know that you are no longer merely human. You are still human, but now, you are "human-plus." [This is why many mystics, including Jesus (who was born as "Immanuel," changed their names. Paul did this, and so did Peter.]
Jesus probably referred to this symbolic identity-change. But there is also the possibility that he simply meant exactly what he said. Jesus is often over-explained; and he might well have meant that Nicodemas had to undergo another birth in a future life, as he was not going to grasp the truth during that one. For mystics believe that God never permanently loses a Soul, that no Soul is ever damaged beyond God's ability to save or recover it, through education.