I came across this statement from N. T. Wright’s commentary on Romans 5.18-21 in which he ably explains the meaning of “eternal life”
The reign of grace goes forward at speed towards its goal, which is the life of the age to come, the time when God will usher in the new creation in which all wrongs will be put to right. (We should note that the normal translation, ‘eternal life,’ where I have put ‘the life of the age to come,’ gives most modern readers the quite wrong impression that Paul is talking about spending ‘eternity’ in a world beyond space, time and matter, in ‘heaven.’ Paul never mentions such an idea. What he has in mind, here and elsewhere, is the bodily resurrection of God’s people to share in the new earth and new heavens which will result from God’s liberation of the present world from decay and corruption.
N. T. Wright, Paul for Everyone: Romans: Part One (London: SPCK 2004), p. 96.