We often hear the expression "he/she has fallen from grace" when referring to a follower of Jesus who has become lukewarm or antagonistic towards their previous Christian faith or lifestyle.
Even Paul accuses the Christians in Galatia who have reverted to following the law as their means of remaining in right-standing before God as having fallen from grace (Gal 5 : 4)
Since grace is God's gift, his undeserved favour toward us, and completely under his control, how can we fall from it? No matter what we do God doesn't withdraw his love or grace. It is determined, guaranteed, by his character.
So what can possibly be meant by the expression "fallen from grace"?
Because it is an action taken by the once-believer, and not an action taken by God, it can only mean that people in that position no longer appreciate God's grace and, of course, have foregone all the benefits that God's grace showers on us.
So, can we fall from grace?
Most definitely YES.
We can turn our backs on what God has provided for us through the death and resurrection of Jesus, as the Galatians did, and miss out on the blessings of living in union with Christ during the ages, the realm of time.
And this would be a great shame to have tasted these blessings and then let them go.
(I don't really understand how people manage to live in this corrupt world with all its dangers and heartaches without a relationship with God.)
But does this mean such a person is eternally lost?
Most definitely NO.
God eventually abolishes death and becomes All in all at the completion of the ages. (1 Cor 15 : 20 - 28)
So although people might miss out on eonian life (age-during life), life exists for all after death is abolished.
And how does this eventuate?
Not sure, but I offer some suggestions in Chapter 5 of "The Really Good News About God".