The Pope's job is unity. All that other stuff is supposed to be in service of unity.

Pope Francis is coming to the land where Jesus was born, crucified and resurrected to do his job. In a land of division, whose overarching symbol has become the wall of separation between Palestinians and Israelis, the patriarch of the West and the ecumenical patriarch of the East are coming together to show the world what unity looks like. This is a pilgrimage to plead for unity.

Pope Francis and Patriarch Bartholomew share a belief in the unity of all people – a conviction that Jesus' prayer "that they all may be one" (John 17:21) was not restricted to any nation or language, race or creed. They share a conviction that human beings must repair the division that has come between humanity and the natural world. When Jesus prayed to restore the nature God gave to Adam in the Garden of Eden, He prayed to unbreak our broken world, to lift sin from our hearts.

It was the priestly prayer of the one true mediator between God and humanity.

That prayer is Jesus' legacy to bishops. That prayer is what bishops do. They pray and act ensure the unity of Christians in their territory. Pope Francis is like any other bishop, but more so. As patriarch of the West and inheritor of a Church established by the Apostles Peter and Paul, Francis prays for the unity of Christians in the world — not just Roman Catholics, but all who know and believe in Christ.

So on the 50th anniversary of an historic meeting between Pope Paul VI and Ecumenical Patriarch Athenogoras I, these two bishops will meet in Jerusalem, the city of peace. Pope Francis and Ecumenical Patriarch Bartholomew I will come together not just to sign an agreement and bring Orthodox and Catholics a little closer together. They will come into a land wounded by divisions to confront the tragedy and sin of our alienation from one another and from the one God who gave us one human nature.

There is a pattern to Pope Francis' itinerary for the three-day visit which begins Saturday, May 24. On day one the Pope will confront division in its most raw, savage and tragic manifestation. Landing in Amman, Jordan, the central moment of his first day in the Holy Land will be a meeting with refugees and young disabled people — people whose lives are being defined by a war in Syria which has produced 2.7 million refugees.

Pope Francis has repeated over and over his disgust with a "culture of waste" and his concern for refugees. It is no accident that the words refuse and refugee sound so similar. There can be no unity until there are no refugees — until we all belong.

The second day seems political. On Sunday, May 25, the Pope meets with Palestinian Authority president Mahmoud Abbas, and addresses the leadership of the emerging state. He celebrates Mass in Manger Square, Bethlehem — an event that will draw all the Christians of the Holy Land together in a massive crowd and at the same time make the case that Christians belong in Israel and Palestine — that this diminishing minority is a precious patrimony of the region.

But the central event of the day will be a private meeting between Francis and Bartholomew with the signing of a joint declaration. There will be more to this than ceremony, or a memory of an extraordinary moment toward the end of the Second Vatican Council when two elders of Christianity came together with a kiss.

The great schism is no mere history lesson. What happened in 1054, when Cardinal Humbert ended a disastrous diplomatic meeting by excommunicating Ecumenical Patriarch Michael Cerularius, who in turn excommunicated Pope Leo IX, was tragedy. It was a wound administered by the Church to the Church, a wound to Christ's body. As Francis and Bartholomew come together they continue a slow process of healing.

On the third day Pope Francis widens the circle of his prayer for unity beyond the borders of Christianity. He meets with the Grand Mufti of Jerusalem, visits the Western Wall of the Temple where Jesus preached as a Jew speaking to Jews, and meets with the two Chief Rabbis of Jerusalem.

Those meetings will be followed by meetings with the President of Israel and an audience with Israeli Prime Minister Benjamin Nethanyahu. The official itinerary does not say Francis will speak to the political leaders about peace. But is there any doubt?

So from confronting the divisions of war on the first day to healing the divisions of history and the sin of the Church on the second and finally carrying the message of unity to all the children of Abraham on the third day, this papal journey leads through the heart of our divisions into the unity of Jesus Christ.