Bible metaphors for different planes, heaven and earth...
The following is an essay that explains Christian, biblical parables about the spirit world, especially heaven and earth. We see that Heaven and Earth co-exist.
We are all spirits interacting in this physical realm which we call "earth." The world you see around you is "earth." Your body is "earth." This is important to understand because the Bible speaks a lot about earth. Heaven is the unseen realm or realm of spirit. Many think of heaven as "up above" someplace, and it is true that heaven is the "higher" or "elevated" place in rank of importance; but, heaven is everywhere - for spirit is everywhere.
Heaven is God and God is spirit. In God we all "live, move and have our being." It is God or "spirit" which is the life-giving force within all. All of us are spirit and exist within spirit; and spirit exists within all of us. Therefore, the heavenly or "spirit" realm co-exists with the earthly or "physical" realm. They are two planes simultaneously in action. We are all spirits interacting in this physical realm and the spirit realm.
The Bible quotes Jesus teaching this core idea: "on earth as it is in heaven." The earthly, physical realm "masks" or "hides" the spiritual realm. Scripture clearly teaches that man is both spirit and body and that "the temple" is a parallel in the bible for the earthly body of man. The jewish temple in scripture has a veil blocking the "outer" (physical realm) from the "most inner" (heavenly realm). This veil hides or covers up the truth of the spiritual make-up of everything, including man himself. I believe the veil to be the "physical flesh" of man, seemingly bound to interacting with this physical world. It is interesting to me that when Jesus gave up his spirit during the crucifixion, it tells us the "veil of the temple was torn in two." I believe the veil that was removed was specifically speaking of Jesus' spirit separating from his body.
So, now that we have an understanding of the spirit and physical realms co-existing within and around all of mankind, let us explore the question of ghosts. What are they? Ghosts are people like you and me, who have crossed over to the other side. Their veil being rent and their spirits freed from being bound by this physical realm. Ghosts are spirits like all of mankind are spirits. They are not to be feared. Scriptures teach we are surrounded by spirits, such as Hebrews 12:1,
"We are surrounded by a great cloud of witnesses."
All one has to do is examine Jesus' ministry and the presence of spirits speaking to him are evident. They speak to us as well and are "messengers." A messenger is an angel for that is what the word "angel" means: "messenger." So, angels are spirits; and spirits are ghosts. All three, related, but just different words used to denote a state or standing - the condition.