You are right, religion is mostly man-made, it mutates and changes with the whim of its creators, particularly secular humanism and other offshoots of "man is the sum of all" kinds of outlooks. But I am not talking about religion(s), I am talking about a relationship with the living God of history. The fact that YOU don't believe something doesn't make it false, nor does it make it "mythology". The word "hell" has been twisted over the years especially in the Middle Ages through art etc, but Jesus used the word "Gehenna" and was alluding to a garbage dump outside of Jerusalem. It was a visual image that would drive home His point about being shut out of the kingdom of heaven, as place where the rubbish was thrown, the fires never went out, and the worms and decay ate the garbage. That is a frightening image. The Jews used the word, "Sheol" and it referred to the grave. The Bible doesn't say a lot about the afterlife in Jewish theology, but the two ideas are not disparate. Non-scriptural writings of the Jews refer to the idea of the righteous and un-righteous dead, and of punishments and rewards for your deeds in life.