'There is but one Greek word beside aiónios rendered everlasting, and applied to punishment, in the New Testament, and that is the word aidios found in Jude 6: “And the angels which kept not their first estate, but left their own habitation, he hath reserved in everlasting chains under darkness unto the judgement of the great day.” This word is found in but one other place in the New Testament, viz. Rom. i:20: “For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead.”
Now it is admitted that this word among the Greeks had the sense of eternal, and should be understood as having that meaning wherever found, unless by express limitation it is shorn of its proper meaning. It is further admitted that had aidios occurred where aiónios does, there would be no escape from the conclusion that the New Testament teaches Endless Punishment. It is further admitted that the word is here used in the exact sense of aiónios, as is seen in the succeeding verse: “Even as Sodom and Gomorrah, and the cities about them in like manner, giving themselves over to fornication, and going after strange flesh, are set forth for an example, suffering the vengeance of eternal fire.” That is to say, the “aidios” chains in verse 6 are “even as” durable as the “aiónion fire” in verse 7. Which word modifies the other?'
'But observe, while this word aidios was in universal use among the Greek Jews of our Savior’s day, to convey the idea of eternal duration, and was used by them to teach endless punishment, he never allowed himself to use it in connection with punishment, nor did any of his disciples but one, and he but once, and then carefully and expressly limited its meaning. Can demonstration go further than this to show that Jesus carefully avoided the phraseology by which his contemporaries described the doctrine of endless punishment? He never employed it. What ground then is there for saying that he adopted the language of his day on this subject? Their language was aidios timoria, endless torment. His language was aionion kolasin, age-lasting correction. They described unending ruin, he discipline, resulting in reformation.'
John Wesley Hanson, The Greek Word ΑΙΩΝ – ΑΙΩΝΙΟΣ, publihser: Locus 7