Philippians 2:12 (written by the Apostle Paul.)
This seems fundamentally wrong for these days and times, in terms of how a Christian ought to approach life.
Of course, this mortal life is tragic - as well as joyous; and we ourselves are weak, and prone to fear, resentment, dishonesty and many other sins - as well as blessed by divine freedom and the capacity for love.
But I am sure that Christians are not intended by Jesus Christ to regard our salvation with fear and trembling; and that - indeed - to do so is a sin akin to despair.
F&T is a sin because it is evidence of a lack of faith in God's goodness and power.
On the contrary; salvation is in our own hands; as is evident throughout the Fourth Gospel - which (to simplify) means that if we want salvation, we can have it.
We get it by following Jesus Christ - and that "following" means after this mortal life; and following analogously to a lost sheep following a Good Shepherd.
For us (here, now) the great thing, the great problem - is Not-at-all about the difficulties of navigating salvation; but much more fundamentally and lethally Not Wanting Salvation.
It is therefore misguided and counter-productive to emphasize the uncertainty of salvation, to make it a matter properly approached in a spirit of F&T.
(As if God was a stern monarch and Judge - rather than God being our loving parent/s.)
What we need and ought to be doing, is not inculcating an attitude of fear and trembling; but instead helping people to want salvation...
Firstly by clarifying what salvation is; secondly by clarifying what are the alternatives.
And then (hardest of all) getting people to think about this matter sufficiently deeply and consecutively, to decide what they really hope-for, for themselves - on a timescale of eternity.