Pope Francis also compared unity between the Eastern and Western Churches as a gradual journey.
"The Church of Rome and the Church of Constantinople are joined by a deep and ancient bond that not even centuries of silence and misunderstanding have been able to break," he said.
They now have "the sacred task to walk back along the path that led to the separation of our churches, healing sources of our mutual estrangement, and to proceed towards the restoration of full communion in faith and love, conscious of our legitimate differences."
Francis praised the patriarch's commitment to increasing awareness regarding the "protection of creation," saying that they were "fundamentally united" in this commitment.
"I found a deep spiritual sensitivity in Patriarch Bartholomew for the painful condition of humanity today, so deeply wounded by unspeakable violence, injustice and discrimination."
Patriarch Bartholomew has also praised Pope Francis on several occasions, notably for his humility, his care for the environment, and his concern for the plight of Christians in the Middle East.
"This is precisely why the path toward unity is more urgent than ever for those who invoke the name of the great Peacemaker," Patriarch Bartholomew said Nov. 30, 2014, and prayed that restoration of full communion between the Catholic and Orthodox churches "will not be prolonged."
He urged greater collaboration, saying that "we no longer have the luxury of isolated action" due to the current persecution of Christians, who are targeted regardless of which church they belong to.
The two leaders "are both greatly troubled by the grave sin against God, which seems to grow by the day, which is the globalization of indifference before the disfigurement of the image of God in man," Francis said.
"It is our belief that we are called to work for the construction of a new civilization of love and solidarity."
"We are both aware that the voices of our brothers and sisters, now at the point of extreme anguish, force us to move more quickly on the path of reconciliation and communion between Catholics and Orthodox, so that they can credibly proclaim the Gospel of peace that comes from Christ."
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