The Concept of Death must be Changed according to Christ Jesus
Death is the most important issue for anybody. Life in this world is the most precious matter for anybody. But Christ Jesus said no to be afraid of death and those who kill you, but to be afraid of the God who can destroy both your bodies and souls in an afterlife.
And fear not them which kill the body, but are not able to kill the soul: but rather fear him which is able to destroy both soul and body in hell (Matthew 10).
For anybody, it is good news that his soul continues to live in a afterlife if his body dies. No matter how poor and unhappy he is in this life, his soul continues to live in a afterlife. And, moreover, although rich men cannot enter into Heaven, poor believers are welcomed in Heaven. What good news for poor men! Besides, Christ Jesus who told this good news was authentic, since He proved that He came from the God.
In this meaning, Christianity is revolutionary, so that it has been able to be sustained for 2000 years.
The Gospel reads: Jesus said unto her, I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live (John 11).
Put simply, if anybody is told by the God that his soul will live in an afterlife after his body is dead in this world, he will be exceedingly relived and rejoiced. So, everybody must be glad as Christ Jesus with authority from the God declares that he will live after death.
Will everybody become unafraid of his death? Not necessarily. If one dies and enters into life after death, he cannot come back to this world to enjoy the material life. Only poor and unhappy men who hate their lives in this world must be glad if they cannot come back to this world after death. But rich and happy people enjoying their happy lives in this world should be afraid of death.
Loving one's own life and his family members means loving his life in this world. But if one loves life after death, he should not love his life in this world. Indeed, poor and desperate men without hope in this world should hate his life in this world. And, only such men can be accepted as followers of Christ Jesus to be loved by Christ Jesus, the Son of the God.
So, life after death is not good news for rich and happy men in this world. It is good news only for poor and unhappy people in this world.
Before entering into Heaven or the hell, one's soul should spend some time in the spirit world; however communications between those souls and living men are basically impossible. Only with approval from the God, one may communicate with souls in the spirit world while living in this world like Christ Jesus.
Nonetheless, the concept of death must be changed again drastically according to the teachings of Christ Jesus.
John 6, King James Version
2 And a great multitude followed him, because they saw his miracles which he did on them that were diseased.
3 And Jesus went up into a mountain, and there he sat with his disciples.
4 And the passover, a feast of the Jews, was nigh.
5 When Jesus then lifted up his eyes, and saw a great company come unto him, he saith unto Philip, Whence shall we buy bread, that these may eat?
6 And this he said to prove him: for he himself knew what he would do.
7 Philip answered him, Two hundred pennyworth of bread is not sufficient for them, that every one of them may take a little.