The above link is to a letter written by Thomas Jefferson to a young man, Peter Carr. If you scroll to the fourth page there is some some interesting advice about religion. I find it noteworthy that Jefferson made no attempt to impose his own opinions.
Great advice. Believe what you will, but understand the arguments against your position, and give each serious attention. Too bad our politicians and religious leaders don't practice this. If they did, I think there would be a lot less suffering and a lot more compromise and cooperation.