Political rivalries and religious and historical sensitivities ensure that the pilgrimage will be marked by constant tension between the pope's spiritual mission and its political repercussions.

Ashkenazi Chief Rabbi Yisrael Meir Lau, for example, declared that the pope's very presence in Jerusalem will imply recognition of Israeli rule over the city. Palestinian sources insist the opposite is true: The fact that the pope is spending all six nights in East Jerusalem, at the residence of the Vatican's diplomatic envoy to both Israel and the Palestinian Authority, means that he actually recognizes the Palestinian right to sovereignty in Jerusalem. Both interpretations, says a high-level Vatican source, are "nonsense."

Even plans for a four-way meeting involving John Paul, Mufti Ekrima Sabri, Ashkenazi Chief Rabbi Yisrael Meir Lau and Sephardi Chief Rabbi Eliyahu Bakshi-Doron, which is intended to promote the seemingly innocuous message of religious brotherhood, are beset by conflict. Initially, the rabbis refused to meet at Notre Dame, the Vatican complex across from the Old City's New Gate, because of the prohibition followed by many Orthodox Jews against entering churches. The Vatican argued that the meeting wasn't being held in a church but in the building's auditorium, and the rabbis relented. Meanwhile, the Vatican has been trying for months to persuade Sabri to show up at all.

And finally there is the Sabbath. An ultra-Orthodox campaign is demanding that the pope cancel his plans to conduct a mass at Nazareth's Basilica of the Annunciation because of the Jewish Sabbath - even though the date was chosen because it marks the Feast of the Annunciation.