The immortality of the soul is actually a Platonic influence on the early Church. I'm in agreeance with Tony on this.
It brings a joy to my heart to see others who have embraced the truth regarding this. You are correct, these are nothing but traditions derived from pagan platonic philosophy, not biblical whatsoever. Platonic did indeed influence the notion of the absolute & indefeasible immortality of the human soul.
There is NO Biblical declaration of death as an endless life in misery as the penalty for sin.
When immortal soulism was adopted from Greek platonism(chiefly through plato,philo), conditionlism was maintained by Christ and the apostles and sustained by the apostolic fathers and the earliest of the ante-nicene fathers and on for centuries. Immortal soulism was not adopted in Christian thought until certain north African platonic church father philosophers espoused it nearly 200yrs after the Christian era had passed. By 400AD, the Christian Church had divided.
Immortal Soulism derived directly from Satan [Gen 3:4], then through Greek Philosophy and penetrated jewry about 150BC, then infiltrated the Christian Church.
Athanasia (Immortality) or Aphthartos (Incorruptible) is never applied to man as a natural possession, and Athanasia is never joined with soul of man.
When Adam and Eve were driven from the Garden of Eden, an angel was posted to guard the tree of life so that sinners would not eat of the tree and "live for ever." Genesis 3:22-24. The teaching that sinners are immortal in hell originated with Satan and is completely untrue.
The only way to live is to get access to the tree of life! And the saved will live forever in heaven where the tree of life will be forever! So the lost cannot live forever in some hellfire because there is no tree of life there!
And without access to the tree of life, there is no immortality, so the lost will DIE and sleep forever! Only the saved will be given immortality. Read 1cor 15:51-55! And without that and without Jesus the lost will not see life. Read John 3:36
So can the lost still LIVE, just as Satan said in Gen 3:4, without access to the tree of life? How can they without access to the tree of life?
The lost will never receive immortality or access to the tree of life which will only be in the new heaven, so they will die the 2nd Death - Greek [apokteino] = kill outright, put an end to, destruction!
The lost cannot live forever in some "hellfire" because there will be NO Tree of life there! And without access to the Tree of Life, there can be no eternal life. Simple as that really!