People have only the most general concept of hell, just as they do of heaven, and that concept is almost so vague as to be none at all. It is like the picture of the world at large available to those who have never been outside their cabins in the forest. They know nothing about its empires and countries, let alone its forms of government, and least of all about society and the way people live in society. Until they know these things, their concept of the world cannot be more than the sketchiest notion, which is practically no notion whatever. Likewise with regard to heaven and hell. In reality, both heaven and hell contain too many marvels to count–indefinitely more than any planet could hold.
The vast number of wonders there can be seen from this one thought: Just as no two people ever have the same heaven, no two ever have the same hell, and all the souls that have ever existed in the world since the beginning of creation flock together there.
Love for the Lord and for one’s neighbor constitutes heaven, as do the joy and happiness it brings. By the same token, spiteful opposition to the Lord and one’s fellow human constitutes hell, as do the penalties and torture it brings.
Hatred comes in countless different types and even more variations on those types. For every variety of hatred, there is a hell.
from Secrets of Heaven, Volume 1, Sections 692,693