For his part, when receiving the relics on Saturday, Ecumenical Patriarch Bartholomew I said that the act confirmed "that insurmountable problems do not exist in the Church of Christ."
The return of the relics of the two Fathers of the Church, both bishops of Constantinople, took place in St. Peter's Basilica, in a solemn liturgy during which the Pope was visibly moved.
During the meeting, a letter was read addressed by the Pontiff to the patriarch, "first among equals" of the Orthodox Churches, in which he said that the return of the relics to Constantinople is "a blessed opportunity to purify our wounded memories, to reinforce our path of reconciliation."
The Holy Father added in the text, which was read on his behalf by Archbishop Leonardo Sandri, substitute of the Vatican Secretariat of State for general affairs, that the gesture demonstrates that it is the "propitious moment" to pray so that God "will hasten the hour in which we will be able to live together, in the celebration of the holy Eucharist, full communion, and thus contribute in a more effective manner to make the world believe that Jesus Christ is the Lord."
"I will never cease to seek firmly and determinedly this communion among the disciples of Christ, as my desire, in response to the will of the Lord, consists in being servant of communion 'in truth and in love,'" the Pope stated in the letter.
After the veneration of the relics, the reading of a biblical passage and excerpts from the texts of the two Doctors of the Church, and a time of prayer, the rite of the handing over of the relics took place.
Following the reading of the Pope's message, Patriarch Bartholomew I publicly thanked him, expressing the "happiness and joy" that this gesture causes in the See of Constantinople and in the whole Orthodox community. The see is in Istanbul, Turkey.
"A sacred act is celebrated today, which repairs an ecclesiastical anomaly and injustice," the patriarch said.
"This fraternal gesture of the Church of ancient Rome confirms that insurmountable problems do not exist in the Church of Christ, when love, justice and peace meet in the sacred 'diaconia' of reconciliation and unity," the Orthodox leader said.
With this act, the patriarch concluded, the Pope has given "a luminous example that must be imitated."
The relics of St. Gregory Nazianzen, who died in 390, arrived in Rome with a group of Byzantine nuns who were fleeing from the iconoclast persecution of the eighth century and in this way saved them.
Those of St. John Chrysostom, who died in 407, were probably removed from the historic Church of the Holy Apostles during the Latin empire of Constantinople, which lasted from 1204 to 1258.