Pope Francis asked all people to work toward a future that lifts up society’s most marginalized, including migrants, the sick, the unemployed and prisoners.
Bishop Gianfranco Todisco said he wrote to the pope last year saying he wanted to return to his work as a missionary.
"I hope that this visit will be an embrace of consolation and of encouragement to all Christians in the Middle East," the pope said.
At Rome's Basilica of St. Bartholomew, a shrine to modern martyrs, Pope Francis presided over an evening prayer service April 22, honoring Christians killed under Nazism, communism, dictatorships and terrorism.
Pope Francis "will affirm that there is a certain solidarity among Christians" and that "we are all related together by Jesus."