"Today we rejoice to commission them and send them forth in pairs as the Lord sent out the 72 disciples," the Pope and archbishop said in a common declaration signed Oct. 5 at the end of an evening prayer service.

The 38 bishops, who are part of the International Anglican-Roman Catholic Commission on Unity and Mission, included: for the United States, Episcopalian Bishop John Bauerschmidt of Tennessee and Catholic Auxiliary Bishop Denis J. Madden of Baltimore; for Canada, Anglican Bishop Dennis Drainville of Quebec and Catholic Bishop Gary Gordon of Victoria, British Columbia; and for Australia, Anglican Bishop John Parkes of Wangaratta and Catholic Archbishop Christopher Prowse of Canberra-Goulburn.

"Let the message go out from this holy place, as the good news was sent out so many centuries ago, that Catholics and Anglicans will work together to give voice to our common faith in the Lord Jesus Christ, to bring relief to the suffering, to bring peace where there is conflict, to bring dignity where it is denied and trampled upon," Pope Francis and Archbishop Welby said in their statement.

The vespers service, in Latin and English, was celebrated at Rome's Church of St. Gregory on the Caelian Hill, the church from which St. Gregory the Great sent St. Augustine of Canterbury and his fellow monks to evangelize England in 597.

In his homily, Pope Francis said God wants the unity of his people "and desires, especially, that pastors devote themselves to this."

Unfortunately, he said, over the course of history, "we have lost sight of the brother who was alongside us, we have become incapable of recognizing him and of rejoicing over the gifts and grace we each have received."

But, firm in the conviction that God continues to walk with his people and call them to journey together, Pope Francis said, all Christians and especially the 38 bishops, are called "to work as instruments of communion always and everywhere."

"When, as disciples of Jesus, we offer our service in a joint way, one alongside the other, when we promote openness and encounter, vanquishing the temptation of closures and isolation," he said, "we work at the same time for both the unity of Christians and that of the human family."

Pope Francis urged Catholic and Anglican bishops and pastors around the world, "before undertaking any activity," to ask, "Why can't we do this with our Anglican brothers and sisters? Can we witness to Jesus working together with our Catholic brothers and sisters?"

"It is in concretely sharing the difficulties and joys of ministry that we with draw closer to one another," he said. "May God grant us to be promoters of a bold and real ecumenism, always seeking to open new paths."

Turning to the pastoral staff of St. Gregory the Great, which is on display at the church, Pope Francis noted that shepherd's staffs have a crook for gathering on one end and a point on the other "to prod those who tend to stay too close and closed, exhorting them to go out." For bishops, that means urging the flock to go out and share the Gospel.

At the end of the service, Pope Francis gave Archbishop Welby a replica of St. Gregory's staff. Archbishop Welby took a pectoral cross from around his neck and gave it, as a gift, to Pope Francis, who kissed it and put it on.

In his reflection at the prayer service, Archbishop Welby said, "When we fight among ourselves as Christians, when we lose the obligation of sharing mercy and forgiveness, we not only disobey the explicit prayer and command of our Lord, but also we become shepherds who devour the sheep, the church becomes a circus for gladiatorial combat in which the losers are shown no mercy."

He told the Pope that the "wonderful power" of the Year of Mercy is its recognition that, in appealing to God's mercy, "we must be merciful to one another" and imitate Jesus in reaching out "to the poor, to the migrant, to the slave, to the refugee."

The prayer service marked the 50th anniversary of the beginning of formal Anglican-Roman Catholic ecumenical efforts with the meeting of Blessed Paul VI and Anglican Archbishop Michael Ramsey of Canterbury.

Pope Francis and Archbishop Welby said in their declaration that, when their predecessors launched the formal dialogue in 1966, they "recognized the 'serious obstacles' that stood in the way of a restoration of complete faith and sacramental life between us. Nevertheless, they set out, undeterred."

While "much progress has been made," new disagreements have arisen, "particularly regarding the ordination of women and more recent questions regarding human sexuality," the declaration said. "Behind these differences lies a perennial question about how authority is exercised in the Christian community."

Still, they said, "we are undeterred," trusting in the Holy Spirit that "dialogue and engagement with one another will deepen our understanding and help us to discern the mind of Christ for his church."

At the same time, they said, the differences "we have named cannot prevent us from recognizing one another as brothers and sisters in Christ by reason of our common baptism."

"We urge our clergy and faithful not to neglect or undervalue that certain yet imperfect communion that we already share," Pope Francis and Archbishop Welby said in their declaration, adding that "not only can we pray together, we must pray together."

"We can, and must, be united in a common cause to uphold and defend the dignity of all people," they said. And Catholics and Anglicans must join forces to end the marginalization of society's weakest members and the growth of "a culture of hate" and violence.