ROME — Meeting 18 young priests and monks from six Oriental Orthodox churches, Pope Francis insisted divided Christians must work together to share the Gospel.

“It is a message that we are called to bear witness to with one another, not against one another or apart from one another,” the pope said June 3 as he welcomed the young clerics who were attending a study week in Rome sponsored by the Pontifical Council for Promoting Christian Unity.

The participants came to the Vatican from Egypt, Armenia, Lebanon, Syria, India, Ethiopia and Eritrea. They were chosen to participate by the heads of their churches, which included: the Coptic Orthodox Church, Armenian Apostolic Church, Syrian Orthodox Church of Antioch, Ethiopian Orthodox Tewahedo Church, Eritrean Orthodox Tewahedo Church, and Malankara Orthodox Syrian Church.

Acknowledging the suffering and persecution all Christians have suffered in some of their countries, Pope Francis gave thanks for their common witness to Christ.

“I think in a special way of all those — and there are so many of them — who sealed by their blood their faith in Christ,” he said. “Thank you for all the seeds of love and hope you have sown in the name of the crucified and risen Christ in all those places that continue, sadly, to be marked by violence and by conflicts that are too often forgotten.”

Noting how the Latin-rite Catholic Church and many other Western Christians were to celebrate Pentecost June 5, the pope shared what he said were four lessons the feast has for Christians, especially in dealing with their divisions.

The first, he said, is that “unity is a gift, a fire from on high.”

While Christians must “pray, work, dialogue and prepare ourselves to receive this extraordinary grace,” the pope said, they also must know that it is a gift of the Holy Spirit and they must open their hearts to receive it.

Pentecost also teaches that “unity is harmony,” not uniformity, Pope Francis said, noting how, after the descent of the Holy Spirit, the disciples spoke in different languages but everyone in the crowd understood.

The delegation of the Oriental Orthodox shows the same thing, the pope said, because their churches have different traditions, but recognize a “communion of faith and sacraments.”

“Unity is not uniformity, much less the fruit of compromise or fragile diplomatic balances of power,” the pope told them. “Unity is harmony in the diversity of the charisms bestowed by the Spirit.”

The third lesson of Pentecost is that “unity is a journey,” Pope Francis said. “It is not a plan to be devised or a project to be worked out around a table.”

“Unity does not come about by standing still, but by moving forward with the new energy that the Spirit, from the day of Pentecost, impresses on the disciples,” he said. It is something that grows as people share their life’s journey, their joys and their sorrows and the gifts they have received from God.

Finally, he said, the descent and power of the Holy Spirit makes it clear that “unity is not simply an end in itself but is closely tied to the fruitfulness of the Christian proclamation: unity is for mission.”

“At Pentecost, the church was born as a missionary church,” he said. “Today, too, the world is waiting, however unconsciously, to hear the Gospel message of charity, freedom and peace,” and Christians must be prepared to share that message together.