Incidentally, I do kind-of like the idea of âage of agesâ to mean something like âking of kingsâ (i.e. the greatest of ages). But as it happens, âage of agesâ is super-rare as a phrase in NT Greek. (Only once that I can find, Eph 3:21.) Almost always itâs âthe ages of the agesâ.
Be that as it may. I think the plural of the phrase indicates an indeterminate but vastly long stretch of natural time. The singular of the phrase (âinto the eonâ, âfor the eonâ) may mean the same thing, keeping in mind that sometimes the reference seems to be for this eon (which we know is going to end) and sometimes for the Day of the Lord to come (which isnât going to end).
I will point out that even when the reference is to this current eon, the event being described may not end when this eon ends. Similarly, the event being described might or might not end in the eon to come (even if that eon itself never ends). Itâs also notable that the Day of the Lord to come, even though it counts as an eon, may itself contain sub-eons, themselves dividable into eons (âinto the ages of the agesâ).
So it isnât altogether simple.
However, I will say that if I was a non-universalist, it wouldnât be based on whether an eon didnât end; similarly, my universalism doesnât depend on whether an eon does end. But I will also say that from a rhetorical usage standpoint, if I didnât have many other reasons to think otherwise and only focused on the rhetorical usage of âeonâ in regard to punishment, I might very easily think this was a witness to the hopeless permanence of the punishment.
As it is, the stress on duration reminds me that even if the punishment is hopeful (and regardless of severity or lack thereof), itâs still going to continue until the soul repents and agrees to cooperate with God in sending away its sins. If I insist on my sinning, it isnât as though I can expect to be freed of Godâs wrath simply because some period of time has passed.
(Although, not-incidentally, that does seem to be how the prophecies of the OT in regard to the sins of Israel were popularly interpreted during Jesusâ day: weâve done our time and now we can come out, right? Well, yes, the time of âGodâs Salvationâ, YSHuA, is coming and is even already hereâbut that doesnât mean youâre going to automatically be set free of the results of punishment. The far more important thing is to be freed from your sinning, and if you refuse to be free of that⌠well, âuntil the last farthingâ is rendered up, you wonât be coming out!)