In the chapter we have a series of contrasts between the new life and the old, the things we will become contrasted to those things we are being saved from.
Yes, but we are not save FROM having a body, we are save from having a body that is corrupted by sin, among other things.
Those good qualities of the new creature (v. 42-44) are: incorruption, glory, power, spiritual.
None of those qualities are opposed to having a body.
Then we read about the originators of the two classes, Adam and Christ. Adam "became a living being". Christ, "a life-giving Spirit."
Adam was created innocent of sin AND possessed a body.
Then we come to a very important, oft-overlooked, detail. Overlooked in application, the origins of these two persons.
"The first man is of the earth (ἐκ γῆς), earthy: the second man is the Lord from heaven (ἐξ οὐρανοῦ) ."
This passage is a continuation of verse 40: somata epigeia and somata epourania now become "ek ges" and "ex ouranou". This preposition (ek, ex - the forms only differ because of euphonics) shows origin. Adam came from the earth, from the dust. This brings to mind the very passage from Genesis. The "Second Adam" came from heaven.
Adam's body was created from the dust (Genesis 2:7) and was given the breath of life from God. Jesus has always been a Person of the eternal Triune God Who dwells in the heavens. He entered into Adam's line, through Mary, and redeemed it. In His death and resurrection, He received a glorified body as the first fruits of the resurrection that we will all receive. We will be righteous in our resurrected bodies (see 1 Corinthians 15:20-23).
Note: In both cases, the origins determine the essence of who these two are - and (v. 48) the essence of their "followers".
No, not "essence," but nature. "Adam" nature is symbolic of the fallen state (not his original, eternal innocent state) that eventually leads to death. In Adam, we have no ability to sustain ourselves eternally. Jesus, from the heavens (aka God), not only is self-sustaining in His life, He can sustain all who enter into His life in their glorified bodies. Remember, it was only after the fall that death entered into human life (Genesis 3, 1 Corinthians 15:21). Originally, Adam and Eve lived in the garden, in bodies, with access to the Tree of Life. Those who are resurrected will live in a similar state, with full access to the Tree of Life again (Revelation 22:2).
says that "we shall bear the image of the heavenly man" (the Second Adam, from heaven).
Did you notice the word "man?" Men have bodies -- even Jesus.
Now here is why I believe our bodies will not be physical. Individual, yes, but not “flesh and blood" or "flesh and bones":
We shall be like Christ. I John 3:2
Jesus was raised with a body of flesh and bones. So we will have a physical body.
He does not need to be like us.
He does not have to bear the scars of His crucifixion either, but He does.
He now has the glory He had with the Father.
Yes, but He also possessed glory as He walked the earth 2,000 years ago.
"And the Word became flesh, and dwelt among us, and we saw His glory, glory as of the only begotten from the Father, full of grace and truth." -- John 1:14
"This beginning of His signs Jesus did in Cana of Galilee, and manifested His glory, and His disciples believed in Him." -- John 2:11
And what exactly is Christ like - according to I Cor. 15?
He is like He was when He came to Earth, before His Incarnation. He is spiritual.
Was Christ fleshly before he came here to Earth? No. He was pure Spirit.
We - according to this passage - will also be like Him.
Pure spirit. Individual bodies, but spirit.
No. Philipians 3:20-21 states:
For our citizenship is in heaven, from which also we eagerly wait for a Savior, the Lord Jesus Christ; who will transform the body of our humble state into conformity with the body of His glory, by the exertion of the power that He has even to subject all things to Himself.
We cannot have part Adam's essence ("dust")...
You have forgotten that we will have glorified bodies.
Christ was physically raised from the dead. If you don't believe that, you are outside the faith. Moreover, He was raised in a glorified body.
...seeing that we could not then "enter into the Kingdom of God".
You have confused the "Kingdom of God" with a spiritual heaven. The kingdom of God speaks of God's active and present rule upon the earth and heavens, not merely a future state. All those who are obedient to Christ in our "Adam" bodies are
ALREADY in the Kingdom of God.
But what about His being, "the Man Christ Jesus"?
This brings us to Hebrews.
The writer of this epistle tells just what is/will be involved by being partakers of the promise in Christ Jesus. Hebrews 12: 18 – 24. Notice especially this part, vss. 22A, 23c:
“But you are come unto Mount Zion … and to the spirits of just men made perfect.”
Apparently, you don't understand that humankind has both a body and a spirit. Before God, our primary issue is not that we have a body that is corrupt and destined to die (that's part of the curse), but that our spirits were -- and sometimes still are -- in rebellion toward God. The writer of Hebrews has been using an extended allusion to the journey of the Hebrews from Egypt to the Promised Land, and he/she is directly referencing the time when the Children of Israel made a covenant with God (Exodus 19). Their problem was not their physical bodies/souls, but their hearts/spirits toward God.
Humanity does not require a physical body. My father and mother, both dead now, both Christians, do not have physical bodies.
Yes, your parents have bodies. Their bodies are no longer living, and depending upon the conditions of their death or processes after their death, their bodies may no longer be in an easily recognizable state. However, they have bodies and those bodies will be restored from the dust into a glorified body.
The normal, natural state for humankind is inhabit a body. During the intermediate state (between physical death and the day of the Resurrection), we may not have bodies in the "dwelling place" (John 14:1-3) or Paradise (Luke 23:43). But the dead will be raised to physical bodies (see Revelation 20:4-6, 12-13).