I've decided to split this into several parts, as I ended up writing quite a bit.
Also, the way I wrote the review changed considerably over the course of reading it.
I started reading this book with the intention of being as open to the possibility of being wrong as possible, but the introduction really irritated me. It didn't feel to me like it was really introducing the book and there were a few things he says that got on my nerves which I have written here. Perhaps I'm being pedantic though, and if so I apologize.
Keller conflates relative morality with arbitrary morality and says this "If morality is relative, why isn't social justice as well?"
He tries to insult moral relativists by comparing them to "the morally upright".
"The people most passionate about social justice were moral relativists, while the morally upright didn't seem to care about the oppression going on all over the world."
Shows more bias here: "Liberals' individualism comes out in their views of abortion, sex, and marriage. Conservatives' individualism comes out in their deep distrust of the public sector and in their understanding of poverty as simply a failure of personal responsibility."
It seems like he is trying to paint liberals as shallow and superficial, while portraying conservatives as "deep" and showing "understanding". I hope this isn't indicative of the rest of the book.
Chapter 1: "There Can't Just Be One True Religion"
"Skeptics believe that any exclusive claims to a superior knowledge of spiritual reality cannot be true."
Wrong. That's not what skepticism is at all, either Timothy Keller is an idiot, or he's never picked up a dictionary in his life (He'd still be an idiot in that case).
Furthermore, the crux of this chapter is arguing against something that skeptics DO NOT CLAIM. The fact that all religions cannot be true is something that skeptics acknowledge and use as ammunition against specific religious claims. The people who claim that all religions are true are spiritualists or new-agers or members of inclusive religious sects. Keller fails miserably in actually arguing against skepticism in this chapter.
Chapter 2: "How Could a Good God Allow Suffering?"
Keller simply parrots C.S. Lewis here and pays no attention to the actual arguments made by skeptics that he claims to be rebutting.
"C.S. Lewis described how he had originally rejected the idea of God because of the cruelty of life. Then he came to realize that evil was more problematic for his new atheism. In the end, he realized that suffering provided a better argument for God's existence than one against it."
Keller just accepts this and moves on. I'm not impressed. He spends most of the rest of the chapter talking about how Christianity can comfort those that suffer. I do not dispute that this may be the case, but it has absolutely no bearing on the truth of the religion, which is the reason I do not believe. Keller seems to assume people all disbelieve for emotional reasons.
Chapter 3: "Christianity is a Straitjacket"
Keller attempts to rebut multiple arguments in this chapter. The first is the idea of relative truth. I do not disagree with him that many contradictory statements can't all be true. He falls flat on his face once again though, because he isn't actually addressing the arguments of skeptics, but rather of spiritualists, new-agers or members of inclusive religious sects. He also goes after the idea of freedom saying "Freedom, then, is not the absence of limitations and constraints but it is finding the right ones, those that fit our nature and liberate us." His justification for this is a quote from C.S. Lewis, so once again he is just parroting another apologist while not actually addressing skeptics. Unimpressive.