Bible-toting Scott Panetti preaches the word of God to a disinterested and largely invisible congregation from his pulpit _ a high-walled prison death row recreation area topped with a ceiling of chain-link fence. «He gets on people's nerves,» said fellow death row inmate Charles Nealy. «He'll just start _ out of nowhere. But the man is a natural Jimmy Swaggart. He's good at it. He'll tell you in a minute you're going to hell.» Panetti's lawyers, death penalty opponents and mental health advocates describe him as severely mentally ill _ and deserving of mercy, according to AP. The double-murderer's attorneys won an opportunity to argue before the U.S. Supreme Court this week that he should not be executed, as Nealy was last month. «Executing a person who cannot understand that his impending death is the result of the crimes for which he stands convicted adds a further dimension to this cruelty,» Panetti's lawyers said in a brief to the high court. Four courts have said he was competent when he fired his trial lawyers. A jury and two courts rejected his defense of not guilty by reason of insanity. He personally argued that only an insane person could prove the insanity defense. The court already has banned execution of inmates found to be mentally retarded and those who committed their crimes when they were younger than 18. The question the high court has agreed to hear arguments on Wednesday is whether Panetti's mental illness has caused him to have a delusional belief about why Texas wants to execute him. -- SPA