Termite,
I think you are right for being concerned about your sons focus right now, especially if you get the feeling that he is afraid of 'displeasing god'.
Pretty much any dogmatic religion whether christianity, islaam, etc works from a basis of fear, although mainstream christianity is better than jws in that at least those who 'accept christ as their personal saviour'' are guaranteed safe harbor, it still damns all the rest.
That's scary.
I would advise exposing him to a variety of belief systems, not inundate him, but just show him that there are many beliefs, and explain that all are valid in their way.
Some eastern philosophy could be invaluable to him, something that stresses individual responsibility in a POSITIVE way. Responsibility for knowing the inherent value of self, the inherent goodness, strength, and beauty WITHIN.
Jiddu Krishnamurti has one of the most beautiful and positive philosophys, his stress is on love, and freedom from fear. Though he will need some help from you as it may be a bit abstract for an 8 yr old, he wrote 'The Life Ahead' (or just 'life ahead') particularly for young people.
Another is Lao Tse . . . you will find a good translation at
http://www.edepot.com/tao8.html
Lao Tse's writing is very brief and poetic, very meditative and soothing.
You won't find any hellfire, gehenna, devil or demons, no god for that matter in these writings. The only hell they speak of is the one people create for themselves in their own minds.
You say your son is a sensitive soul, well sensitive people are the strongest in the world . . . unless someone convinces them to turn over their power to another source, then they are at risk of becoming victims of their own sensitivity.
My best advice would be to lead him AWAY FROM THE HELLFIRE, I can't agree that it is harmless (though it certainly is for SOME). Fear based, condemning religions have wrought some of the most evil suffering on the world.
Best luck to you and yours,
raven101