I really feel kind of hesitant to delve into this discussion and would like y'all to understand up front that I don't want to knock anyone's religious beliefs. I'm very firmly attached to my own and respect everyone else's right to believe whatever they choose, as long as the practice of their beliefs doesn't hurt anyone but themselves. And preferably not even themselves.
Okay, so the Vineyard Movement. It's not a bad thing in and of itself, but you know how people can take a thing and run with it? So you have Baptists and extreme Baptists, Mormons and extreme Mormons, etc, etc, and so on down the line. Just some examples, not knocking anybody. So here's a basic overview, Wikipedia version:
Association of Vineyard Churches - Wikipedia, the free encyclopedia
It describes the Vineyard Movement as "a neocharismatic evangelical Christian denomination... rooted in the charismatic renewal and historic evangelicalism. Instead of the mainstream charismatic label, however, the movement has preferred the term Empowered Evangelicals... to reflect their roots in traditional evangelicalism as opposed to classical Pentecostalism. Members also sometimes describe themselves as the "radical middle" between evangelicals and Pentecostals..."
And here's a non-Vineyarder's story of visiting a Vineyard church in 1995 and again six years later:
http://faithinconsistent.wordpress.com/2011/09/11/the-vineyard-will-deliver-you/
Obviously, having never visited the Jamisons' church, I cannot say how it compares. But there are extreme sects in just about every denomination, and Oklahoma has certainly been fertile ground for them.
My own upbringing was in a very prim and proper white-glove Presbyterian church but, as a teenager, I did occasionally visit a Pentecostal church with friends, and that place totally blew my young mind. It was just a very, very different style of worship than I was accustomed to.
Coming from the religious training I've had, if I heard someone talking about demons and spirits on the roof and whatnot and being perfectly serious about it, I'd be reaching for the phone to call a mental health hotline. But someone else, of a different background, might find such topics of conversation absolutely normal.
And I'm thinking, to the Jamisons, that sort of conversation might have been completely ordinary, and not necessarily a sign of mental illness.