Amy was interviewed by Fox News on May 2nd, 2009 to discuss the Roloffs Christian faith. The Fox News interviewer said Little People, Big World and the Roloff family have earned high marks because not only is the show family oriented, but it is faith oriented and they don't hide their Christian Faith.
Amy answered that the show is real and about their family; faith is apart of their family. Amy said that is very encouraging to people and regardless of what a person's faith may be, it is very similar to what everybody else has with the foundation in their own family.
Presumably because of this interview, we're receiving a lot of inquiries today asking what faith are the Roloffs or inquiries about Amy Roloff's Christian faith. Some people might have seen the interview, but are not very familiar with the Roloffs and trying to find out more.
I think it is fair to say that on the show religion is not made into a major issue. The Roloff kids attend a private Christian school which has been shown and talked about several times. They've mentioned the kids being involved in various youth Church groups and occasionally (perhaps 4 or 5 times) they've shown the Roloffs saying a prayer before a meal (although family dinners are rare for the Roloffs). On a recent show in which Jacob said "Molly F'd us" for telling on him, Amy made him write out a passage in the Bible as his punishment.
In print and interviews however, the Roloffs are much more out-spoken about their Christian beliefs. Many of Amy's speaking engagements are Christian events and the Roloffs 2007 book "Little Family, Big Values" went into to detail about their beliefs and God - which included statements such as Jeremy stating he didn't drink or do the other bad stuff teens are known for because of his faith in God (although there was contradictory evidence to that seen on his Myspace account over the years).
You can watch the Fox News interview clip with Amy about the Roloffs Christian faith here.