Rome: Declaring "we are all migrants," Pope Francis visited the Greek island of Lesbos with a message of hope for those seeking asylum in Europe, 12 of whom he took home with him to the Vatican.
His one-day trip to Europe's migration hotspot culminated dramatically when three Syrian refugee families, all Muslim, returned with the pontiff to Rome.
The Pope told reporters that his gesture was "a drop in the ocean" but hoped that afterwards, "the ocean will never be the same again".
"All refugees are children of God," he said aboard the papal plane on its flight back to Rome.
The departure of the 12 refugees, who will be housed by the Vatican, was the climax of an emotional visit that saw migrants kneeling in tears before the 79-year-old Roman Catholic leader.
"You are not alone... do not lose hope," the Pope, who was accompanied by Ecumenical Patriarch Bartholomew and Archbishop Ieronymos, the head of the Church of Greece, said at the Moria registration centre, where around 3,000 migrants are being held.
The vast majority have requested asylum but will likely be deported under a controversial agreement reached last month to tackle Europe's refugee crisis by sending all irregular migrants who land in Greece back to Turkey.
As the Pope was escorted through Moria to meet a select number of migrants, one man broke into tears as he knelt at the pontiff's feet, requesting his blessing.
Another woman who slipped past security to approach the pontiff also broke down in tears as he paused to listen to her.
Other migrants gathered outside held hand-made signs that read "We want freedom", "Let my people go" and "Papa cherche a nous sauver" ("Pope, try to save us").
A group of small children presented the Pope with a dozen drawings.
Lesbos is one of the first ports of call in the EU for the hundreds of thousands of asylum-seekers who have fled war, poverty and persecution in the Middle East and Asia across the Aegean Sea via nearby Turkey in the past year.
The religious leaders said a prayer at Lesbos harbour in memory of the hundreds of migrants who have drowned during the voyage in overcrowded smuggler boats.
"Merciful God... though many of their graves bear no name, to you each one is known, loved and cherished," the Pope said.
Earlier they signed a declaration calling on the international community to "respond with courage" to the humanitarian crisis and calling on religious communities to step up efforts to assist refugees.
The Pope stressed that migrants were not numbers but people with "faces, names and individual stories" who were preyed on by "unscrupulous thugs" and called for "resolute" efforts to clamp down on arms trafficking.
"The world will be judged by the way it has treated you. And we will all be accountable for the way we respond to the crisis and conflict in the regions that you come from," he said.