I strongly believe children shouldn't be raised as any religion, let them grow up and decide for themselves. my parents are religious, and I think we would have a better relationship if they weren't. Ironically I think the tension comes from the same place, they are extremely idealistic and see religion as the route to social justice, where as I see religion as the cause of many problems, judgemental with an unfair influence over peoples lives, which offends my own sense of social justice, but I would never be able to express my views as it is their entire life.
This response might be off topic or it might not be, people with aspergers tend to be logical, not stick to conventions so some may be less susceptible to religion, that combined with stubbornly sticking to their own principles could cause tension. So I guess that is the key thing, flexibility, educate them about religion but don't expect them to believe it, don't create an environment where they can't express their own beliefs because they will find it hard enough to express themselves.