The author blurb describes Jonathan Cahn as the leader of "a worship center made up of Jew and Gentile" in New Jersey. One of the testimonials inside the front cover calls him a rabbi, and you wouldn't know otherwise until you got more than 90% of the way through, where a clear invitation to confess faith in Jesus is given. All but two of the Bible quotes are from the Old Testament, and one of the two New Testament quotes (both near the end) is not footnoted; you had to know it. That's not all bad, but from a Christian perspective, building a message of doom for America from the Old Testament alone seems to have theological problems. Jesus Christ is the final revelation of God to us.
Nevertheless, Cahn has done an awesome job of getting the mystical numbers to line up. His two-line forward says "what is contained within the story is real." Endnotes identify sources for most of the quotations. I don't have the resources to check most of them, but the notes add credibility. What I did look up was true. Except for the fictionalized seals.
I regularly read Biblical Archeology Review, so I know something about the subject. Ancient Hebrew seals are pressed in mud (he got that part right), but they are less than an inch in diameter and the mud is not baked, so they are very fragile. Cohn's initial seal was two inches in diameter [p.6] and mailed to the main character (with no return address? After 9/11? The Post Office would have refused to accept and to deliver it), and he carried it around in his pocket for weeks. A real 500BC seal would have crumbled into dust from the stress. But on p.243 his prophet character tells him this is an actual seal from Jeremiah's personal scribe. The seals are not the story, they are an invented vehicle to carry the 9/11 coincidences (I use the word literally, to mean things that match, not to mean accidents), astonishing dates and places that line up the 9/11 event to an ancient Biblical prophecy.
For example -- I checked this out -- St.Paul's Chapel in New York City was constructed ten years before the American Revolution, and was one of the few buildings not burned down by the British during that war. Immediately after his inaguration, George Washington walked a short distance to St.Paul's, where he and all of Congress prayed for God's blessing on the new nation. That same church is across the street from Ground Zero, but was undamaged by the debris. Instead, a sycamore tree in the church yard took the fallout and was knocked over. It was subsequently replaced by an evergreen tree in a eerie reprise of Isaiah 9:10, "The bricks have fallen down, but we will rebuild with dressed stone; the sycamores have been felled, but we will replace them with [evergreens]." Most of the book repeats different national leaders quoting this one verse in defiance of 9/11, just as Israel originally used the same words in defiance of God's judgment.
The prophetic message of the book is not a bad message: Repent! God still wants all people everywhere to repent. Now is a good time to start. Eleven years ago would have been a better time to repent, but better late than never. Israel did not repent, as Isaiah reported in the verse, and were subsequently destroyed and never heard from again. Our national leadership -- including not just the Party now in power, which has made sin the cornerstone of their platform, but also the other Party which has implicitly done the same thing (with different sins), and also the influential leaders of the media and shapers of public opinion -- are moving in the wrong direction. God could indeed destroy this nation in our lifetime.