If this were a painting or a drawing instead of a book, I would classify it as a caricature. The author draws a picture with words of Paul the Apostle that over emphasizes his characteristics.
We get hints of the nature of Paul from the scripture--that he is zealous at whatever he did 'whether killing Christians before his conversion, or winning people to Christ after his own conversion...that he was prone to be argumentative' that he was demanding of others as well as himself.
The author takes those hints of Paul's nature and greatly overemphasizes them, making Paul seem rather grotesque. He does the same for the other characters in the book: Priscilla and Aquila, Peter, James, Timothy, Luke, etc.
The chapter format was interesting, however. The author titled each of the 99 short chapters with the character's name who was telling that portion of Paul's story from their point of view. They were sometimes relating a totally fictional account---sometimes quite loosely paraphrasing a portion of scripture. I found I enjoyed the chapters written from Paul's perspective most of all. He sounded intelligent, dedicated, loving--not at all like the caricature the author would have him be.
I will most likely not read anything else by this author. This book, at least, was not the type of romantic historical fiction I am fond of.
I did learn from 'Paul' though. The author did manage to give some logic and clarity to some of the ambiguous portions of Paul's writings in scripture.