We had these discussions so often, I can't understand why we always discuss this particular topic, even if Jesus had said the wicked will be punished for a decade, that wouldn't automatically mean they would be saved after the decade, a defense for universalism should not be stressed whether an aeon is always finite or not, and as only God is eternal without beginning and end, we could say, that eternal punishment is nothing but divine punishment and that it says nothing about the lenght of this punishment at all.

Amen!!
Just as ETERNAL life comes "from God" so does EVERLASTING punishment come "from God" who ~IS~ ETERNAL!!
That which is "eternal" (aionios) is that which is connected to that which is SPIRITUAL (NOT SEEN)
2Co 4:18 While we look not at the things which are seen, but at the things which are not seen: for the things which are seen are temporal; but
the things which are not seen are eternal.
The only reason that I feel that it is "appropriate" to limit even that which is "aionios" to TIME is because of scriptures themselves seem to connect even this unseen, spiritual realm to time (rather than eternity):
2Ti 1:9 Who hath saved us, and called us with an holy calling, not according to our works, but according to his own purpose and grace, which was given us in Christ Jesus
before the world began,
"προ χρονων αιωνιων" or "
pro chronos aionios" (before times aionios)
Tit 1:2 In hope of eternal life, which God, that cannot lie, promised
before the world began;
"προ χρονων αιωνιων" or "
pro chronos aionios" (before times aionios)
In both cases, above, it is the adjective and not the noun that is being used. It is used in the plural in both cases and clearly connects to "time" (chronos) and purposed that were set and promised that were made "before" the eons (ages, including that which is visible and that which is invisible) were established.