Pope Francis on Monday met with representatives of a centuries-old Marian order of priests and brothers dedicated to mercy, encouraging them to persevere in their service to the marginalized by clinging to the “strength and joy” of the Gospel.

“We do not rely on our own strength, but instead we always entrust ourselves to divine mercy,” the Holy Father told members of the Mercedarian Order during a May 2 audience in the Vatican's Consistory Hall.

“If God is present in your lives, the joy of bringing his Gospel will be your strength and your joy. God has also called us to serve within the Church and in the Community. Let us keep to this common path,” he said.

The Mercedarians are in Rome ahead of their 800 year anniversary in 2018 for their General Chapter where they will elect new governing body and decide on projects for the next six years.

The Order of the Blessed Virgin Mary of Mercy, or the Mercedarians, was founded in 1218 in Spain by St. Peter Nolasco as a community dedicated to a life of prayer based on the Rule of St. Augustine in service to Christians imprisoned by Muslims.

Along with the vows of poverty, chastity, and obedience, the Mercedarians take a fourth vow to give up their lives to those in captivity and in danger of losing their faith. Today, they work in 17 countries including the United States, India, Brazil, Italy, and Spain.

The Mercedarians work to serve the most marginalized members of society: prisoners, the hospitalized, addicts, and those living in poverty-stricken neighborhoods. They also have a special emphasis on safeguarding the faith in families through parish work and education.

Pope Francis praised the order’s work over the centuries, noting that the priests and brothers became “like hostages” to the marginalized, dedicating their lives to “bring them consolation, to suffer with them, completing in their own flesh what was lacking from the passion of Christ.”

Although “there is much to remember” of the Order’s long history, “this memory must not be limited to an exposition of the past,” the Holy Father said, but should instead “be a serene and conscious act that enables us to assess our achievements, without forgetting our limits and, above all, to face the challenges that humanity presents to us.”

“The true life of the order must be sought in the constant effort to adapt and renew, so as to be able to respond generously to the real needs of the world and the Church, while remaining faithful to the perennial heritage of which (the Mercedarian Order) is a depository,” he said.

The Mercedarians, through their religious vows, have been made prophets who have received a “gift of the Holy Spirit for the service of the Holy People of God,” the Pope said.

“You have also received a gift, and have been consecrated for a mission that is a work of mercy: following Christ, bringing the good news of the Gospel to the poor, and the liberation of captives,” he said.

By following the Holy Spirit in service of the marginalized, “we must make ourselves small, unite ourselves with the prisoners” and in doing so will “encounter true freedom” of recognizing the Redeemer in the form of the “poor and captive.”

Pope Francis exhorted the Mercedarians not to neglect to “proclaim the year of grace of the Lord to all those who are sent to you,” namely, those facing persecution for their faith, victims of human trafficking, and school children.

“I offer my blessing to each one of you and for the entire Mercedarian family, and I beg you not to forget to pray for me,” the Roman Pontiff said in closing.