[RightWhale]

Yeah, we know that. In reality, how is that implemented?

[DoughtyOne]

I believe that only God knows the human heart.  I believe the answer to what you ask would be something like this.

Those who lived before Christ or never heard the story of salvation through faith, but had lived up to all the truth they were exposed to, would likely be deemed to be pure in nature.  It could be possible that God would grant them salvation based on their devotion to good works.  It would be reasonable to assume those living as good a life as possible, would accept any truth presented by God after salvation and live according to that.

It has always seemed to me that in the end days, there would be a period of religious persecution.  In that time all those living would have to contemplate the nature of Christ and Christianity, and during that time choose either to accept Christianity and Christ's sacrifice, or be found wanting when judgement was finalized.  The final period of persecution would have to be global and focused on the truly pure.  It would be up to each of us to consider the actions of the powers that be vs the followers of Christ at that time, to search our own souls and to act accordingly.

This would seem to cover every soul both past and present.

[El Cid]

John 14:6 Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me.

Yeah, we know that. In reality, how is that implemented?

I'd say, 'read the tagline below', but I'm not sure I understand your question...