Jerusalem Syndrome is actually a real thing. Visitors (and, less frequently, locals) really do occasionally find themselves believing they are characters from the Bible or messengers from God. Most frequent sufferers? Protestant tourists from the United States and Scandinavia. But Jews are not immune, either.
So whence the disorder? “Those who succumb are unable to deal with the concrete reality of Jerusalem today,” wrote the Israeli psychiatrist who coined it.
A gap appears between their subconscious idealistic image of Jerusalem and the city as it appears in reality. One might view their psychotic state and, in particular, the need to preach their universal message as an attempt to bridge the gap between these two representations of Jerusalem.
So, basically, if you go to Jerusalem wanting to make the imperfect city into a perfect utopia, then you suffer from Jerusalem Syndrome? Sounds a lot like George Mitchell to me! Ba-zing!