That's the way the Bible declares that Jesus told it. Lest you think that this is a solitary reference that has some other meaning other than what the context gives it, let's look at the evidence from several other scriptures. And many of them that sleep in the dust of the earth shall awake, some to everlasting life, and some to shame and everlasting contempt. Where their worm dieth not, and the fire is not quenched. Ordinarily a worm feeds on a rotting object and then dies.
Fire consumes the fuel that's feeding it and when the fuel is consumed, the fire goes out.
Some of you are already experiencing a foretaste of hell because you won't deal with that unfinished business. The first two words you wrote on the page of 1996 were, if only. When Jesus talks about fire, I believe that He's talking about the unremitting heat of passion that can never be satisfied. Most of you know that if you don't nail your passions to the old rugged cross, they get hotter and hotter, consuming every waking moment of your life with unrelenting torment. Many of us have cried out for death so that we can have release from the fires of passion which rage within us.