Plot Summary: Mack's youngest daughter is abducted and killed. Though her body is not found, evidence of her death is found in an abandoned shack in the forest. Some time later, he receives a note from God to meet Him at the shack. What transpires is one man's struggle with life's heartaches and God's role in this. It is one of the most popular examples of narrative apologetics in recent days. (Spoiler warning!)
General Analysis: I found The Shack to be a captivating read, particularly once I had gotten through the first few chapters. It nobly attempts to address and often answer some of the most difficult questions of depravity, liberty and God's power over all. What I found particularly refreshing is that the author did not shy away from the tough questions, nor did he simply regurgitate overly-simplistic pat answers. This boldness has caused a number of readers to recoil with alarm, but I believe such courageous attempts should be thoughtfully considered and critiqued. Hence, this review.
Objections: I try to be generous to those who thoughtfully wrestle with understanding the faith, but I found two issues that ought to be called out. First, one of the more controversial features of the story is that God is personified as an African-American woman. This is explained as God's choice to reveal Himself in this way to Mack, to shatter his preconcieved ideas about God, formed by tradition and not by Scripture (in particular, that God is an old white guy). The author rightly notes that God is not simply male nor female, but that both together bear the image of God (Gen. 1:27). While this alone might could pass, it does cross the line of orthodoxy in the next frame. The book shows the full Trinity interacting with each other, talking together and so on. Here's the issue: the relationship between God and Jesus is revealed in the Bible exclusively as that of God the Father and God the Son. Jesus always refers to God as Father, and portraying their relationship to one another in any other way ventures into bad theological waters. It changes the way that we view the relationship between the first and second person of the Trinity, a relationship that the Gospels spend a decent amount of time discussing.
Second, the claim is made that their is no "boss" or authority among the Trinity. While it is true that no member of the Trinity is of less worth or power than the others, there is an authority structure or role for each member of the Trinity. "Now I want you to realize that the head of every man is Christ, and the head of the woman is man, and the head of Christ is God" 1 Cor. 11:3. (See also John 16:12-15) God has established authority and order in His Creation, not as a demeaning thing, but as an opportunity for submission and love. The Shack shows a misunderstanding of the idea of authority, possibly even contempt toward it, missing the Bible's approach by a fair margin.
Commendations: Despite the issues above, I found quite a bit of the answers given in this book to be well-developed and acceptable. While the negative issues have received much of the attention, the good deserves more recognition. Solid, biblical truth is affirmed repeatedly, and often it is the extra-biblical traditions that are rightly attacked and corrected.
Most importantly, however, is the central idea of the story: God is love, and He desires to have a real, loving, and personal relationship with every person on the planet. He is not a distant redeemer, but One who is willing and available to be known by His people. This truth redeems all the short-comings of The Shack.
At least, that's my opinion.