In reference to an interest in angels that was proliferated in the late 80s early 90s, one writer said:
"...awesome, frightening creatures have been taken out of the Bible and turned into cuddly little things that sit on coffee tables and perpetually smile at us, ...a picture of modern American theology for the masses."
The research that has been done on individuals claiming personal encounters with divine intermediaries (angels and the like) report little fear, no sense of awe, and a resulting experience of comfort and reassurance with no accompanying demands on their life or life-styles.
This interest in encountering God (god, gods, angels, spirits, etc.) will always exist in humans and within culture - no matter how secular, scientific, or rationalistic they become.
What is interesting is how these encounters often become projections of the hopes, longings, and beliefs of the culture around them. It is a spiritualized image of what is observable in the world around them every day.
I am certainly not a "burn down The Shack" kind of guy, but I think this is where some of the concern about the book comes from. It can be read as a god-on-your-side, personally-therapeutic encounter with God. It was/is popular because it strikes a cord deep within the hearts of many people in our own cultural setting. For that reason it deserves to be thought about carefully (just like the fascination with Oprah Winfrey or Vampire romance novels). But what also should be considered is the decidedly "American theology for the masses" that is at play in that story as well. Most encounters with God with angelic beings in the Bible left the individuals with a sense of fear, awe, and with a serious demand placed on their life to be about God's purposes in the world. Not that God's love does not heal or that we should not seek His help in recovering from our brokenness. But the challenge is to discern how much of what we long to see in God and get from God is simply part of what the culture has conditioned us to live for.
This post is not about The Shack. I enjoyed it well enough. I know I risk a major distraction in using it, but it was just the most recent example I could think of for a popularized tale of one man encountering the divine face to face. This post is, rather, about how we can co-opt God into our own ideologies. This is about how the "consuming fire gets domesticated into a candle flame providing religious atmosphere and warm feelings but no power for purification" (Don McCullough, The Trivialization of God).
A couple of books I am about to read on this point that may interest you:
Christian America and the Kingdom of God, Richard T Hughes
Radical: Taking Back Your Faith from the American Dream, David Platt
One that I have recently finished that helps to trace the spiritual impulses of American culture within the last 60 years is After Heaven: Spirituality in America Since the 1950s, Robert Wuthnow.
ps I also realize how a few of the responses against The Shack are also cultural projections of the god people want (see, I went on making this about the shack when i didn't want it to be!)