I just finished this book by Piper. It is about 120 pages. The first few chapters are easy reading to get everyone acquainted with the theology of justification by faith. The book was written to respond to an increasing number of "evangelicals" who have turned away from the doctrine of the imputed righteousness of Christ to the believing sinners account. Gundry is the primary representative for this recent movement. Therefore, Piper spends most of his time dealing with him and his writings. The last chapter is lengthy and quite deep. It is not for the casual reader. The premise of Gundry is this: the righteousness that people have is actually their faith. When Paul says that you are justified by faith, he actually means that your faith is counted as righteous. The premise of Piper is this: the righteousness that people have is actually the righteousness of Christ imputed to their account. Thus, when Paul says that you are justified by faith, he actually means that your faith is that which joins your account and Christ's righteousness. Faith is that which receives Christ's righteousness. Gundry probably does not see his problem. If a person's faith is actually righteous, then the person has some good to him that will be paid to him because God has become the debtor. I recommend this book to anyone. It will certainly be a part of my children's Bible curriculum.