I just read the book, yes, I am a bit behind the times. I am on to Angels and Demons next.
The book did not offend me at all, but then again, I am not a Christian. The "royal bloodline" makes a lot of sense though. And this is a theory that is out there, not just Brown's. Jesus was Jewish, and a Rabbi. In the Jewish religion Rabbi's are supposed to be married. It is shall we say encouraged. So I find that theory very believable. It was a fact that Jesus was a decendant of King Solomon and King David. This lineage is kept track of, since the Jewish Messiah is said to be born of that lineage.
Let's see, the Freemasons exist, Knights of the Templar, Opus Dei, Priory of Scion these are all real organizations. Granted what was written about them was a fictional account.
The bible. Ok, the Old Testament was written by a group of Hebrews called the Pharisses ( I am sure I am spelling this wrong) and they wrote their versions of history and stories. For example, the story of the Macabees and Chanukah is not in the Old Testament. They weren't of the Pharisses sect, so they got booted. I am sure the New Testament is similar. They men writing it, put in the Gospels they wanted in. It was their version of history and what happened. The dead sea scrolls, the Gospel of Mary, and the ones they just found from Judas, all tell different versions of what happened in their times.
I am sure 2000 years from now, some people will be discussing the Bill Clinton VS G W Bush presidential years!!
Just remember, there are 3 sides to every story. His version, her version, and the truth. Since most of us aren't objective, and just see things, or interpret them differently, stories get scewed. That is life.
I liked what Dan Brown wrote about Faith. It is just believing in something even if there is no proof to back it up. That is what believing in religion is.