Uh, lots of religions use guilt and/or fear to keep their members in line. How many Christians would be religious if it were not for fear of an afterlife in H@ll?
Most people are Christian or Jewish because they believe in the faith. I personally view Christianity as the best path to a good life more than anything. The teachings of Jesus are brilliant and if people abided by them we wouldn’t have the problems we have today.
If there is no justice, either in the here or hereafter, there is actually no reason to be a good person other than any particular circumstances you find yourself in.
For example, you may not molest a child, but only because you fear the physcical consequences imposed by its brother, or society, not because you think it is wrong.
Or, if you live in, say AFghanistan, you have no reason to restrain yourself.
Forgive me, but that bit of "conventional wisdom" is ridiculous.
I was a complete agnostic. I didn't first become religious and only then believe in Hell because the religion was "trying to keep me in line."
I became a Christian because I experienced Hell. First, I saw clear as a bell that whatever the heck is wrong with the world is not due to any political, economic, or philosophical system but because the human heart is broken. Wounded. There's something seriously wrong with it. I can't see God, but I'd have to be an idiot not to see original sin.
Second of all, I've led a very happy, contented life in many ways. But when the sheer emptiness, the sheer nihillism, the sheer meaninglessness of it all hit me like a ton of bricks one day, that's when I found Hell. Despite all the good things in my life, I was becoming Hell. I felt it. I knew it. It was either change my direction, or become something I truly truly hated.
Christianity didn't keep me perpetually in fear of something happening in the future. It saved me from something that was happening already.