As Christmas approaches, Christians around the world turn to thoughts of the Holy Land and the great figures in the Bible.

For some who come on a visit, the religious energy is enough to make them recite scriptures on the street or claim to be King David or Jesus.

The phenomenon is known as the Jerusalem Syndrome, though psychiatrists disagree whether it can affect otherwise healthy people, or causes only those predisposed to psychoses to believe they have seen the Messiah.