I am not happy with this book. It is not giving a proper understanding. The author is trying to lead you through the Scriptures, in that way it will be helpful.
The late Stephen C. Doyle O.F.M. had some interesting interpretations that made me think. Not sure I totally agree, but he made a good point: The best commentary on the Bible is the Bible. He used lots of Scripture to back up his views, but he also used traditional methods such as the historical record and Papal encyclicals.