Francis earlier Sunday called for the urgent observation of a limited ceasefire in Yemen reached in December and for food and medicine to get to its people, who are suffering the world's worst humanitarian crisis.
In comments to reporters on his flight back to Rome, Francis said he sensed "good will to bring about a process of peace" in Yemen during his meetings with officials from the UAE, Saudi Arabia's key ally in the war.
The Pope was driven up in his Kia to the front door of the palace, where he was greeted by Sheikh Mohammed bin Rashid Al-Maktoum, vice president and prime minister of the UAE, and Sheikh Mohammed bin Zayed, crown prince of Abu Dhabi.
Jesus, Francis said, "did not ask us to build great works or draw attention to ourselves with extraordinary gestures".
"The cry of these children and their parents rise up to God", he told followers in St Peter's Square.
On Monday, the pope met with Emirate leaders and signed a joint declaration together with Sheikh Ahmed el-Tayeb, the grand imam of Cairo's Al-Azhar University, condemning "acts of murder, exile, terrorism and oppression" carried out in God's name.
Pope Francis warned that unless people of different religions come together to seek "concrete paths of peace", the future of humanity itself will be in danger.
Yet the historic visit of the Pope is the direct outcome of that simple act of fraternity.
"I am thinking in particular of Yemen, Syria, Iraq and Libya", the pope said during an interfaith meeting in Abu Dhabi attended by Sheikh Ahmed al-Tayeb, the world's top Sunni Muslim cleric.
For the Gulf Arab region where public displays of non-Islamic faith are restricted, the hymns of "Halleluja" booming out from speakers marked a milestone and evidence of the Emirates' much touted assertions of its tolerance for other faiths.
The pope's highly publicised 48-hour visit to the United Arab Emirates will also include an open-air mass on Tuesday for 135,000 of the Muslim country's million Catholic residents, set to be the largest public gathering in the country's history.
Out of the roughly nine million people living in the UAE, the Catholic Church estimates as many as one million are Catholic.
Despite making some reforms, the kafala (visa sponsorship) system continues to tie migrant workers to their employers - meaning those who leave their employer can face punishment for "absconding". "It becomes a place of belonging" in a country where foreigners can live, work and practice their faith but will never gain citizenship.
Some 80 percent of the people living in the United Emirates, including nearly all the Catholics, are foreign workers.
For his part, the pope thanked his Emirati hosts for protecting freedom of religion and conscience. Francis exclaimed. "I liked that". It hopes the deal will pave the way for talks to end the war.
The first Catholic church was established in 1965, six years before the formation of the UAE. Standing beneath a portrait of Sheikh Zayed, Pope Francis cited the declaration of the Second Vatican Ecumenical Council in 1965 - issued in the very year the church of St Joseph's opened: "We can not truly call on God, the Father of all, if we refuse to treat in a brotherly way any man, created as he is in the image of God".