This is an old-fashioned look at a Hebrew lexicon and two Greek lexicons, but in an easy-to-read format for nontechnical readers of the Bible. The definitions are wide-ranging and unexpected.
Biblical Hebrew Lexicon
Brown, Driver, Briggs Hebrew lexicon online says that the main Hebrew is ‘olam and is used 439 times. It is surprisingly versatile:
(1) noun masculine long duration, antiquity, futurity
(2) of past time:
a. ancient time: days of old; ancient people; old waste places
b. ancient gates; from of old; the ancient; long in them.
b. the long dead
c. of God, former acts; as redeemer; of love; judgment, dominion; long silence;
d. of things: ancient hills
e. plural: years of ancient times; in olden times.
2. a. Indefinite futurity, with preposition forever, always (sometimes = during the lifetime);
b. = continuous existence,
c. of divine existence: presumably everlasting
d. of God’s covenant: everlasting covenant (but the NT says those old covenants are for an age)
e. of God’s laws: The Bible says that the laws are everlasting, like the Aaronic priesthood, but the NT teaches that ceremonial law has an expiration date, while moral law does not.
f. of God’s promises: his word: everlasting
g. of relations between God and his people, ׳לע presumably everlasting, but the NT says the old relationship lasted for an age.
h. of Messianic dynasty and king: presumably everlasting, since this is still going on through Christ.
i. = indefinite, unending future:
j. after death: presumably it goes on forever, unless God resurrects people, in which case death lasts only an age.
k. = age (duration) of the world:
l. plural intensive everlastingness, eternity;
m. special phrase: from everlasting to everlasting; from now and for ever;
So yes, ‘olam can mean “everlasting” or “forever” in some contexts, but mostly and much more often it means “an age” or a “long duration.”
Source: https://www.studylight.org/lexicons/hebrew/5769.html, which has lots of Scripture references.
Now let’s turn to Greek, the language of the New Testament.
Lexicographers Bauer, Arndt, Danker, and Gingrich produced a lexicon that is considered by many to be the authoritative for the Greek NT. Their lexicon is abbreviated as BDAG.
The Greek noun for age or eternity is aiōn. It is pronounced eye-own, and we get our word aeon from it; it is used 122 or 123 times in the NT.
Here is what BDAG says of the noun.
(1) (a) A long period of time, without reference to beginning or end, of time gone by, the past, earliest times;
(b) Of time to come, which if it has no end, is also known as eternity (so commonly in Greek literature Plato and others);
(2) (a) a segment of time as a particular unit of history, age, the present age (nearing its end);
(b) The age to come;
(3) The world as a spatial concept, the world;
(4) the Aeon, as a person the Aeon (Eph. 2:2; Col. 1:26; Eph. 3:9).
Let’s now explore the adjective aiōnios (pronounced eye-oh-nee-oss and used 71 / 70 times).
(1) Pertaining to a long period of time, long ago;
(2) Pertaining to a period of time without beginning or end, eternal, of God (Rom. 16:26; Heb. 9:14);
(3) Pertaining to a period of unending duration, without end.
So, the noun and adjective have versatile meanings, but it is clear that “eternal” is attached to God; if not attached to God it mostly means “a long time” or “an age.”
The term for “eternal” is not nailed down. In fact, in the majority of times, the NIV translates the noun (aiōn) more often as “age” or “world” instead of “forever” or “eternal.” And the NIV translates the adjective (aiōnios) “eternal” for the duration of hell, but further studies show that this is begging the question or assuming one interpretation over another. It could mean that hell lasts for an age, but not eternally.
You can decide.
How does this post help me grow in Christ?
Words are fluid, within a range. But they are not so fluid that their meaning is totally unclear. In some cases the Hebrew and Greek terms studied here can mean, depending on the context, “for an age” and in other cases it means “eternal” or “forever.”
Growth in Christ means we have to study the Scripture thoroughly and understand the context.
So how does these terms relate to the doctrine of hell?
First, let’s not call people ‘heretics’ if they believe in universalism, which says that after suitable punishment in hell people will be reconciled and restored to God.
And let’s not call them ‘heretics’ if they believe in annihilationism or terminal punishment, which says that after a suitable punishment in hell, God makes them no more–they are disintegrated into nothing; they pass into nonexistence, which is a kind of endless punishment.
Second, believe it or not, these two alternative theories to the traditional one (eternal, conscious torment) have plenty of Scriptures to support them. Eternal conscious torment in the flames of hell for your kind-hearted grandmother who never got around to receiving Christ does not have as firm a support in Scripture as one may believe. Click on the relevant related posts below, to find out why.
In any case, whichever theory you light on, be kind to those who don’t share your opinion. Personally, I don’t consider the details about punishment in the afterlife to be an essential doctrine because reasonable and intelligent and sincere Christians can marshal biblical evidence for their various theories.
Therefore, in essentials, unity; in nonessentials, liberty, in all things, charity (love).