Hi Rachael,
Cranks like this arise from time to time. The policy of the moderator is non interference. Therefore, the best thing to do is to block messages from this sender in your email client program. Pretty much all email programs allow you to filter undesired senders individually.
In my opinion, the best way to remove such noise from a list is for all to simply ignore it and not respond. The psychology of a lot of these people is that sadly they crave attention, and posting lunatic religious rants always stirs people up and they get the attention they crave. By utterly ignoring them they are deprived of oxygen and they go on to the next list. Even this email feeds his attention-getting craving, so enough!
The other way to discourage the offending behaviour is simply to laugh at him. There is no more powerful thing than Satire! :-)