What does "to appeal from the Hell" mean?

The following passage is an excerpt from [*god is not Great*](https://en.wikipedia.org/wiki/God_Is_Not_Great) by Christopher Hitchens: >Pre-Christian hells were highly unpleasant too, and called upon the same sadistic ingenuity for their invention. However, some of the early ones we know of —most notably the Hindu— were limited in time. A sinner, for example, might be sentenced to a given number of years in hell, where every day counted as 6,400 human years. If he slew a priest, the sentence thus adjusted would be 149,504,000,000 years. At this point, he was allowed nirvana, which seems to mean annihilation. It was left to Christians to find a hell ***from*** which there was no possible ***appeal***. (And the idea is easily plagiarized: I once heard Louis Farrakhan, leader of the heretical black-only “Nation of Islam,” as he drew a hideous roar from a mob in Madison Square Garden. Hurling spittle at the Jews, he yelled, “And don’t you forget — when it’s God who puts you in the ovens, it’s FOREVER!”). What does he mean by "appeal from hell"?