My apologies for following the errant thread of the subject matter earlier.
I returned to re-read your posts concerning the use of the words eternal, and the the immortality of the soul. I found most helpful what C. S. Lewis wrote in 'Mere Christianity' about our mortal perception of time and eternity as opposed to that of the living and eternal God who created us. If we (mortals) limit God and the corresponding spiritual realm the to the contraints of our view/experience of time, it becomes even more difficult to understand the truth of His Word concerning things eternal and immortal. Some here have defined the soul so as to include or be equal to the 'body'. However, the soul and body would, by implication of scripture, be separate and distinguishable (Matt 10:28) entities -- the body (flesh) now corruptible since the fall of man, and the soul (essence) as a portion of that eternal 'image of God' into which we have been made (created). God is not under the limits of this construct of time in which we live and He has so wonderfully created. As such, He is able to see 'the beginning from the end', already knowing those who are His sheep and the goats (Matt 25:32-33) and knowing those who will " go away into eternal punishment, ....." Matt. 26:46
(eternal -- Grk 'aionios' meaning 'perpetual, everlasting' -- Strongs concordance)
In which of Jesus' other parables does he use personal names, and describe details as He does in His story of Lazarus in the bosom of Abraham, speaking to the rich man in Hades? Is He not speaking directly to the 'scoffing' Pharisees? Could it be that they might know the actual person of whom Jesus spoke? Would this not provide a stinging conviction among them of His power and authority in the spiritual realm? Did Jesus not raise a 'Lazarus' from the grave, restoring his soul to a body which had 'fallen asleep'? Could it have been a prophetical look forward for someone present? God only knows. But it does appear to be more of an account than a parable, in my observation at least.
The eternal fire of Sodom and Gomorrah (Jude v.7 ...in undergoing the punishment of eternal fire) which you have described in the physical sense, did have a physical ending on Earth. As evidenced by Jesus' proclaimation (Luke 10:12 and following) that it will be "more tolerable in that (judgement)day for Sodom, than for that city", implies that spiritual punishment is yet to come (and apparently in varying degrees). When Jesus spoke these things, the fires of those cities had, of course, long been extinguished. Reason would therefore dictate, by chronology and tense, that Jesus was pointing forward to this coming punishment, which cannot be interpreted as anything other than eternal, perpetual, everlasting.
Personally, I do not revel in the thought of eternal punishment -- what a fearful thing, to fall into the hand of our Holy God. But that it, isn't it? We fall into His hands -- He will judge our hearts (not the bodily ones ;-)) He is a Holy God, full of all power and authority, yet He cannot do everything -- He cannot lie, He cannot contradict himself -- He is Truth. So when He says 'eternal' I have no other recourse than to believe His Word. His Holiness demands it to be so -- not because He wants it so, but because He loves us so much that He would let us choose. In 2Peter 3:9, we understand that God is 'not willing' (Grk - 'me boulomenos', not wanting, not wishing) does not express a decree, as if all will be saved; instead that while He longs for to be saved, but knows that many will reject him.
C. S. Lewis agains illustrates the concept well when he describes the parent who instructs the child on how to clean up his room after himself, explaining the necessity of the task, and the penalty for not following the parental will. When the child fails to clean the room, it is not the will (want, desire) of the parent that the room remains untidy, but a result of the choice that the child has made (free will). The penalty will be paid. In our case, our righteous and holy God determines the punishment, and is kind enough to tell us quite clearly, whether we choose to accept it or not.
God bless, and thank you for your indulgence, Al