(CNN) -- After a joyous welcome from the gathered faithful, Pope Francis celebrated Mass on Saturday at a stadium in Jordan on the first leg of a Holy Land trip intended to promote a message of unity.
His trip has been billed as a "pilgrimage for prayer," with its roots in faith, not politics.
But in a region where religion and politics are so closely intertwined, his every remark will take on an added significance.
The Holy Land trip, also taking in Bethlehem and Jerusalem, is the first for Francis as leader of the Roman Catholic Church, and just the fourth for any pontiff in the modern era.
Thousands of believers packed the International Stadium in Amman for the Mass in what is a majority Muslim nation with a significant Christian community. Many cheered and waved as the Pope arrived.
In his homily, Francis spoke of the need for tolerance and diversity, and urged everyone to put aside grievances and divisions.
"The mission of the Holy Spirit is to beget harmony ... and to create peace in different situations and between different people," he said.
"Let us ask the Spirit to prepare our hearts to encounter our brothers and sisters so that we may overcome our differences rooted in political thinking, language, culture and religion."
Small groups of cheering supporters earlier lined the road, waving flags and chanting "Long live the Pope" as Francis' motorcade left the airport in Amman at the start of his three-day visit to the region.
The Pope's first stop was at al-Husseini Royal Palace in Amman, where he met with Jordan's King Abdullah II.
In televised remarks after that meeting, Francis paid tribute to Jordan's efforts to promote interfaith tolerance and to the welcome that the small nation has given to Palestinian refugees and, more recently, those fleeing war-torn Syria.
Francis said it was "necessary and urgent" that a peaceful solution was found to the crisis in Syria.
He also called for a "right solution with regard to the situation between Israel and the Palestinians." Middle East peace talks recently stalled despite high-profile efforts by U.S. Secretary of State John Kerry to push them forward.
"I grasp this opportunity to renew my esteem and respect for the Muslim community and show my appreciation for the work carried out by his Majesty the King, which is promoting further understanding between peoples of different faith and communities of different faith," Francis said.
His visit marks the 50th anniversary of the landmark meeting between Pope Paul VI and the then-spiritual leader of the world's Orthodox Christians, Patriarch Athenagoras, in Jerusalem.
While in Jordan, Francis will greet some of the 600,000 Syrians that have fled since the start of the civil war in 2011 as well as refugees from Iraq. He will also visit the River Jordan, where many Christians believe Jesus was baptized.
Accompanying Francis on his trip are Rabbi Abraham Skorka, who co-wrote a book with the pontiff, and Sheikh Omar Abboud, who leads Argentina's Muslim community.
The religion of the Pope's traveling companions, both of whom hail from his home country, Argentina, is no coincidence.
"It's highly symbolic, of course," said the Rev. Thomas Rosica, a consultant to the Vatican press office.
"But it also sends a pragmatic message to Muslims, Christians and Jews that it's possible to work together -- not as a system of checks and balances but as friends."
In Bethlehem, Frances will greet children from refugee camps, celebrate Mass in Manger Square, lunch with Palestinian families and visit the site of Jesus' birth. The Pope is expected to call for a Palestinian state, which has long been Vatican policy.
And in Jerusalem, the pontiff will meet the city's grand mufti and chief rabbis, visit the Western Wall and Yad Vashem, a memorial to the Holocaust, and lay a wreath on the grave of the founder of modern Zionism, Theodor Herzl. He will also celebrate Mass at the site of the Last Supper.
CNN's Delia Gallagher contributed to this report.