I will now quote various passages of Scripture to shew aion or aionios has the definite meaning of "for ever," or "eternal," in English. No one who has examined its use in Greek questions that it is used for life, or the whole period of a man's existence till he breathes his last; nor that it may be used for ages or periods, looked at as a whole. The question is, Does it not properly mean eternal or for ever, and that where age and age-long would have no sense? Thus Matthew 21: 19, of the fig-tree: Let no fruit grow on thee eis ton aiona. "For the age" has no sense. It never was to grow. So Mark 11: 14. That eternity is not grasped by man as a definite idea is true, because definite is finite, and man, being finite, cannot grasp what is in-finite. It is known only as that which is absolutely; or negatively as that to which end is denied. Again, Mark 3: 29, oik echei aphesin eis ton aiona. What age? It is not in the age, as some have fraudulently translated it, but "has not ever forgiveness." It is not any particular age; the eis allows no such sense, and the ton would require some particular age, which even so would leave no sense to eis. It can only mean here "for ever." There was a present age and age to come, o aion outos, and o aion o mellon, and well known to the Jews, the olem hazeh, and the olem havo; and an increased measure of forgiveness was looked for in Messiah's age. This sin could be forgiven in neither; no additional increase of forgiveness was looked for beyond Messiah; and each measure belonged to its own age; it was not a prolonged process, but what occurred in each as proper to it. But eis ton aiona, can only mean "for ever," though "for ever" may be used metaphorically when there is no withdrawal of the gift or promise, and the effect cannot last longer than that to which it applies. The gift has no limit (it is, as Aristotle says, apeiria), the existence of that to which it applies may. I do not lend it, I give it for ever; yet what I give, or the person to whom it is given, may cease to exist; but the gift is for ever, without repentance, out and out.
128 So John 4: 14, shall not thirst "for the age": is that the meaning? or never? John 6: 51, 58, "live for ever"; John 10: 28, not perish "to the age": is that the sense? John 13: 8, thou shalt not wash my feet "to the age!" A multitude more may be quoted to the same effect; some with the modified sense I have spoken of above of absolute gift and calling never to be retracted. But eis ton aiona never means "to the age" in any case.
Take 1 Peter 1: 23, 25, logou zontos theou kai menontos eis ton aiona. Does it last only "to the age" (applying it to the logon, not to theou as some do)? So verse 25, rema menei eis ton aiona. So 2 John 2, the truth shall be with us "to the age!" So Jude 13, wandering stars, to whom is reserved the blackness of darkness eis ton aiona. Here again "to the age" has no sense.