I'm going to make a statement and then attempt to explain how I get there:
IMO immortality for CREATED human beings does not mean we cannot be destroyed - soul and body - by the God who created us. Only God has life that is indestructible in Himself and only the Son of God possesses in Himself His own immortality, according to scripture.
I believe the churches misconstrue what it means to be immortal. To be immortal simply means your body is alive forever - UNLESS you stop abiding in the Vine of life - the source of life of all creation, and sin, and the God who CREATED you, destroys you - soul and body - by fire.
Through my studies in the scriptures I've come to realize that immortality - which is associated with being alive in a human body that does not die - is dependent upon having eternal life,
and it's extremely important to carefully consider this, because firstly, life exists IN God alone, and only because God exists. Without the existence of God there is no life. Paul said, "In Him (God) we live | are alive [zao], and move, and have our being; For we are also his offspring." (Acts 17:28).
Life is in God alone - and in the Logos:
"The Logos of God was in the beginning with God. In Him was life [zōḗ], and the life [zōḗ] was the light of men." (John 1:2 & 4).
"And the Logos became flesh, and dwelt among us, and we (John the apostle and his companions) beheld his glory (the glory as of the only begotten of the Father, full of grace and truth.)" (John 1:14).
Secondly, among human beings, only the Son of God has life in Himself:
"For as the Father hath life [zōḗ] in himself; so hath he given to the Son to have life [zōḗ] in himself." (John 5:26).
Eternal life is in Christ alone.
The eternal life in Christ that God has given to CREATED human beings who do not have eternal life in ourselves, is in Christ alone, and He alone possesses eternal life in Himself:
"God has given to us eternal life [zōḗ], and this life [zōḗ] is in His Son: He that has the Son has (eternal) life; and he that has not the Son of God has not (eternal) life [zōḗ]." (1 John 5:11-12).
No CREATED human being has eternal life in himself. The eternal life of any created human being who has been given eternal life is in Christ: Jesus told those who believed in Him:
"I am in my Father, and ye (will be) in me, and I in you."
(John 14:19b-20b)
In Colossians 1:27 Paul talks about "the mystery which has been hidden from ages and from generations, but now is made manifest to his saints, which is Christ IN you, the hope of glory."
So if anyone - any CREATED human being - has been given eternal life by God, your eternal life is not in yourself, but IN CHRIST, who alone has life IN HIMSELF. Christ in you = eternal life in you.
Jesus said, "The kingdom of God does not come with external evidence that can be observed. Nor will they say, 'Look, here it is!' or 'It's over there!' For take heed, be discerning, and perceive this: The kingdom of God is within you." (Luke 17:21).
Jesus also told us that unless we are born of the Spirit of God we cannot see or experience the Kingdom of God.
Paul said, "When Christ, who is our life [zōḗ], shall appear, then shall ye also appear with him in glory." (Colossians 3:4).
IMPORTANT: This explains why, even though (BEFORE he sinned, and BEFORE death came to mankind), Adam was alive, had eternal life, and was able to eat of the tree of life freely (he was immortal), yet he died the moment he sinned.
Satan had said to him, "You will not surely die".
Thirdly, I have come to realize that - just ike Adam (BEFORE he sinned and BEFORE death came to mankind) - though we be immortal following the resurrection of our bodies, yet because we will never possess eternal life in ourselves (only God does), CREATED human beings can never possess our immortality in ourselves:
Immortality: To live | be alive [zao] forever (never dying).
"He (Christ) alone possesses immortality and lives in unapproachable light, whom no human has ever seen or is able to see. To him be honor and eternal power! Amen." (1 Timothy 6:15-16).
"For as the Father has life in Himself, so He has given to the Son to have life within Himself" (John 5:26).
So part of the New Covenant is that CREATED human beings will once again have immortal bodies when our dead bodies have been resurrected from the dead, but since Adam sinned and died - and forever - the death of CREATED human beings is the evidence of the fact that only Christ possesses (His own) immortality because only Christ has eternal life in Himself.
No created human being possesses eternal life in itself. Only Christ possesses eternal life in Himself.
No created human being who does not possess (eternal) life [zoe] in itself can of itself live | be alive [zao] forever, without dying (possess its own immortality).
Satan told mankind: "You will not surely die".
"For this reason Christ died [apothnesko] and rose again from the dead [anistemi], and lived again [anazao: lived again in a body that is not dead], so that he may be the Lord of both the dead [nekros] and living [zao: those who are alive in a body that is not dead]." (Romans 14:9).
Jesus said, "Do not fear, I am the First and the Last, and the Living One, and I became dead, and behold, I am alive for ever and ever, Amen. And I have the keys of hades and of death." (Revelation 1:17-18)
"God has saved us, and called us with a holy calling, not according to our works, but according to his own purpose and grace, which was given us IN Christ Jesus before the world began, but is now made visible by the appearing of our Saviour Jesus Christ,
who has broken the power of death, and has brought life (zoe) and immortality to light through the gospel." (2 Timothy 1:9-10).
Jesus the Messiah is the Vine of (eternal) life [ZOE]. Eternal life is in Christ, who alone has life [zoe] in Himself. Only God has life [zoe] in Himself (John 1:2 & 4; John 5:26; 1 John 5:11-12); and He said:
--- I am the vine, ye are the branches. Abide in me, and I in you, because if a man abide not in me, he is cast forth as a branch, and is withered; and men gather them, and cast them into the fire, and they are burned, and as the branch cannot bear fruit of itself, except it abide in the vine; no more can ye, except ye abide in me. He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing. --- (John 15:4-6, verses rearranged).
So, in other words. I do not believe in the validity of your argument regarding CREATED human beings who are alive in human bodies that do not die, not being capable of being destroyed both soul and body in the fire by the CREATOR who created us. I.O.W, I do not believe in OSAS either now, or when we have become immortal.
I believe the churches misconstrue what it means to be immortal. To be immortal simply means your body is alive forever - UNLESS you stop abiding in the Vine of life - the source of life of all creation, and sin, and the God who CREATED you, destroys you - soul and body - by fire.