"Athanasia occurs only in 1 Corinthians 15:53f (referring to resurrected believers)"
The WT applies this verse to the anointed as shown by this article (note also that perfect humans can die):
Questions
From ReadersWhat
is the difference between immortality and everlasting life?Endless life will be enjoyed both by anointed ones receiving spirit life in heaven and by humans whom God declares righteous for life on the Paradise earth. So if you think about the outcome, immortality in heaven and everlasting life on earth result in basically the same thing-living forever. There are, though, some comments about immortality that can be made.
The Greek word translated "immortality" (athanasia) is formed from the negative a and from thanatos, meaning "death." Immortality thus has the basic sense of ‘without death,’ or deathlessness. Understandably, Jehovah is the absolute source of all life and is immortal. (Psalm 36:9; 90:1, 2) This is confirmed by the fact that his glorified Son, who now "is the reflection of [God’s] glory and the exact representation of his very being," is described as "the King of those [men] who rule as kings and Lord of those who rule as lords, the one alone having immortality." (Hebrews 1:3; 1 Timothy 6:15, 16) No creature can take Jesus’ life as an immortal, which makes him different from humans or spirits that can die. Further, we read: "Now that [Christ] has been raised up from the dead, [he] dies no more; death is master over him no more."-Romans 6:9.
Though immortality is, in a sense, everlasting life, immortality apparently implies more than that its possessor will live forever. It seems to indicate a particular quality of life, and it is linked with incorruption. The Bible says about spirit-anointed Christians who receive the heavenly reward: "This which is corruptible [in its human body] must put on incorruption, and this which is mortal must put on immortality. But when this which is corruptible puts on incorruption and this which is mortal puts on immortality, then the saying will take place that is written: ‘Death is swallowed up forever.’"-1 Corinthians 15:53, 54.
Still, the Bible does not provide much detail about the quality of life termed immortality. We do know that mortal humans-even perfect humans having the prospect of endless life on earth-must eat and drink to maintain life, or they die and their bodies experience corruption. (Genesis 2:9, 15, 16) No doubt immortality involves a quality of life that does not need to be sustained like that. Thus it could be said that all who become immortal are not subject to death or that ‘death is master over them no more.’ That would harmonize, too, with their receiving incorruptibility, indicating that their spirit body or organism is inherently beyond decay, ruin or corruption. (Compare 2 Corinthians 5:1; Revelation 20:6.) In these ways a difference might be seen between immortality and everlasting human life.
Jehovah God is the perfect Judge who rewards anointed ones with immortality. When he in his boundless wisdom and insight determines such ones to be completely tested and unquestionably qualified for immortality, we can trust that they will forever be faithful. All whom Jehovah judges worthy of endless life, whether as immortal spirits or as perfect humans, will be able to worship him forever. Thus, in the final analysis, both everlasting human life and immortality in heaven result in endless life.-John 17:3.
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"What about all the texts which use aiôn or aiônios to describe the future life of believers or the life of God? In such cases, by your synthetical approach, those words do mean "eternal/everlasting," don't they?"
If you've read the links I provided you know that when God is the subject then aion is assumed to be a never-ending age. As for us mere humans aion would mean a long, long indefinite time, but not forever. If ohlam had meant everlasting to the jews they could have translated it as aidios (which clearly means everlasting) in the septuaguint. Instead they chose aionios which means age-lasting.
thinker
(she-may ha-shah-MA-yeem) n. Highest Heaven. The third heaven.
(she-may ha-shah-MA-yeem) n. Highest Heaven. The third heaven.