I don’t think anyone disagrees the Bible says Jesus and his pals thought the “end” would come during their lives. They expected the end of the world momentarily.
Author/Professor Bart Ehrman ( www.erhmanblog.org ) explains how the thinking of Jesus people at that time differs from today’s version of Christianity. It begins with the observation Jesus was a member of a Jewish faction know as apocalypticists.
The apocalypticists did not see a move from life on earth to a later life in heaven or hell. They had a timeline, separating time from that of the evil and sinful period to a later period when God got everyone on the right track.
All of this would take place right here on what we call, Mother Earth. Ehrman says the apocalypticists had a horizontal plain.
Jesus and the cast of characters that followed ran into the same problem as own current end of world celebrity, Harold Camping. You may recall Camping, a Bible radio guy, predicted the world would end, May 21, 2011.
The end of the world didn’t happen either for Jesus or the Christians that followed immediately after. They, like Camping, could not say, generation after generation, “The world will end any day now,” and keep their support.
So, the faith morphed to Plan B. That was to reinterpret the apocalypse story to mean there was a heaven and a hell. The story changed from a horizontal to a vertical plain.
Heaven and hell came out of that solution.