Roofus,
In my case, it’s because many of the uses of “eonian” don’t really fit that concept. The secret hushed since the times of the age to come, which the God of the age to come has now authorized us to proclaim…? The hills of the age to come collapse at the coming of Jehovah, because (unlike them) His ways are of the age to come?? The priesthood of Phineas and his descendants is of the age to come??? The cultic responsibilities and rights of the priesthood are of the age to come???
The bars of the age to come surrounded Jonah when the sea monster took him down to the depths of the sea???
I realize that an argument can be kind-of made that the Son is the God of the age to come (whether unitarian, trinitarian or modalist) where He reigns as merely an ultimate authority figure over those who have not yet repented and so have not yet come to see Godship as anything more than an exercise of power over those who are less powerful (the way they would be Gods if they could)–after which the Son ceases reigning (in some substantial sense) and hands over all things to the Father. And of course there are many examples where the meaning “of the age to come” would fit fine. But the term usage doesn’t fit other examples very well.
I don’t think I emphasized as strongly as I could have how even in Jonah the imprisonment comes from God, mainly because I didn’t want to bird-dog off into an argument for Jonah being a figure for post-mortem repentance and salvation. (I’ll mention that again in my post-debate commentary.) And obviously I agree in principle that the punishment and the life is, in some sense, that of the age to come–although in some real sense we have that life already in this age!
But my goal in that arm of the discussion–which I don’t think TFan ever quite understood–was to argue (1) that “eonian” cannot and by context does not have a necessary intrinsic meaning of never-ending (a meaning of some kind of duration is useless for TFan’s argument, although he seemed to think at the end that a meaning of any duration at all clinched his argument ); and that (2) there are at least two alternatives readily available for understanding the term usage, one of which can be used broadly but is neutral to the purpose of exegeting non-universalism (or universalism for that matter), and the other of which (long duration) is flexible enough that superficially similar yet substantially different meanings can (and provably were) used by both NT and OT authors in close contrasting topical contexts.
As to why TFan doesn’t accept “pertaining-to-or-of the age to come”, you’d have to ask him. My guess is that he would answer that since the age to come does not end, so what?–that would mean the things described in that fashion are endless, too, right?
(I got the impression from how he handled my rebuttal material there, that he hadn’t really studied the term usage much (if at all) before the debate, and wasn’t prepared beforehand to deal with that topic, although he took some honorable swings at compensating for that lack on short notice. )