'Eternal' in the Bible

And angels who did not keep their own designated place of power, but abandoned their proper dwelling place, [these] He has kept in eternal chains under [the thick gloom of utter] darkness for the judgment of the great day,

wild waves of the sea, flinging up their own shame like foam; wandering stars, for whom the gloom of deep darkness has been reserved forever.

and keep yourselves in the love of God, waiting anxiously and looking forward to the mercy of our Lord Jesus Christ [which will bring you] to eternal life.