The trip comes during a period of heightened tension between Israel and the Vatican. First, Cardinal Renato Martino described Gaza as a "big concentration camp." Any such reference to the Holocaust touches a raw nerve in Israel.
The German-born Pope then reinstated excommunicated British Bishop Richard Williamson, who denies the Holocaust. Benedict later reversed the move, spoke out against anti-Semitism and met with Jewish leaders for reconciliation.
Still lingering, however, is the controversy surrounding Israel's charge that wartime Pope Pius XII was silent during the Holocaust. A photo of Pius at Jerusalem's Yad Vashem Holocaust Memorial has infuriated the Vatican because it says he was "neutral" in the face of the Nazi genocide. The Church maintains that Pius used quiet diplomacy to try to save the Jews.
The Pontiff's trip will include visits to the Western Wall and the Islamic Dome of the Rock in Jerusalem, Jesus' birthplace in Palestinian-ruled Bethlehem, Nazareth, and the site on the Jordan River where, according to tradition, Jesus was baptized. The Pope will end his visit with a Mass in Galilee.
Benedict said he will pray for, "the precious gift of unity and peace for the Middle East and all of humanity," as he visits the holy sites.
Archbishop Antonio Franco, the papal nuncio in Jerusalem, said Benedict will meet with Israeli, Palestinian and Muslim leaders: "The intent of the Holy Father's visit is to express his solidarity and closeness to the people of Israel and Palestine, and through them, all the people of this region."
But the Pope will be walking a tightrope.
The rabbi of the Western Wall in Jerusalem's Old City says Benedict should not wear a cross to the site during his visit. The Pope wears a cross in all public appearances, but Rabbi Shmuel Rabinovitch said the symbol is an offense to Jews who were persecuted for centuries by the Church.