I have read through the entire Bible twice. The second time I read it I focused on references to hell, the devil and satan. It's very interesting but I think these Christian teachings about hell are derived from a different source other than the Bible. The Bible is a hard book to understand. I do consider the possibility that I missed it.
However I do have a secular understanding of the verse Matthew 5:22 which says, "But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the
judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire." I think that if you spend many years noticing how stupid, or how retarded, or how dumb, or how ignorant, or how foolish other people are then you will eventually suffer immensely. You will start viewing yourself in this way and you will start feeling that other people view you this way. It is a complete hell on earth experience. It's a horrific way to live.
I do believe anybody who calls someone a fool is in grave danger. The Bible says, "hell fire" but I know of no scripture to cross reference that term to describe exactly what hell fire is.
I think this hell tradition comes from Mormon doctrine (I've read the Book of Mormon too) or maybe it predates Mormonism. Maybe the Christian vision of hell derives from Greek or Roman mythology? I don't think there is enough Biblical evidence for Hell in the way that it is described in churches. This is one of those passed down traditions that nobody knows and very few people challenge.