"Forever and ever"

One argument annihilationists sometimes use is that the “eonian” terminology of Scripture doesn’t mean “eternal” because it has reference to a two-age scheme: this age and the age to come. As such, that says nothing about the duration of the coming age. It just indicates one age followed by another age. An epochal distinction.

But there are two or three basic problems with this argument:

i) Standard NT lexicons give “eternal” as a definition of aionios. Cf. BDAG 35b (#’s 2-3).

ii) Even on a two-age scheme, the age to come is supposed to stand in contrast to this age, which is characterized by mortality. If the present age represents death, the age to come represents a deathless existence.

Of course, the annihilationist may claim that a deathless existence only pertains to the saints, and not to the damned. That, however, is not an implication of the two-age scheme. At best, that’s an overlay.

iii) In Revelation, we have an iterative formula: “forever and ever,” “unto the ages of the ages” (eis tous aionos ton aionon, e.g. 19:3; 20:10).

That’s not a two-age scheme. It's not a contrast between the present age and the age to come. Rather, the whole phrase denotes the age to come. An expansive, open-ended formulation which indicates everlasting duration.