Pope Francis canonised Swedish nun Mary Elizabeth Hesselblad and Polish monk Stanislaus Papczynski, the first to be proclaimed saints during the Jubilee of Mercy, in a ceremony attended by thousands of pilgrims at St. Peter's Square, on Sunday.

During the Mass, Francis said: "The Church today offers us two of her children who are exemplary witnesses to this mystery of Resurrection. Both can sing forever in the words of the Psalmist: 'You have changed my mourning into dancing, O Lord, my God, I will thank you forever,''' reports Newsmax.

Hesselblad, a nurse and Lutheran convert to Catholicism, is the second Swede to become a saint, following Saint Bridget who was canonised in 1391. During her time, she saved the lives of several Jewish families by hiding them in the Roman convent where she was superior. She died in Rome April 24, 1957 and was beatified April 9, 2000 by St. John Paul II.

In 2004, she was awarded the Righteous Among the Nations, an award given to non-Jews who helped Jews during the Holocaust.

Papczynski, a Polish priest born in 1631 and beatified by Pope Benedict XVI in 2007, was the founder of the first men's religious order dedicated to the Immaculate Conception. He supported hospitals and shelters for the poor in the 17th century. His crowning achievement was founding the order of Marian Fathers, which preached the cult of Holy Mary.

Maria Pilar, a Bridgettine nun from Spain, said the canonisation of their foundress is not only a recognition of her sanctity, but also gives publicity to "the example of a person who lived for God and sought the truth since she was a child – she was Lutheran and sought the truth as a young girl.''

"St. Maria Elizabeth was called to offer a lot in the ecumenism of the Church, so that all religions would be one in Christ, not just in Spain," Pilar told the Catholic News Agency (CNA).

Meanwhile, Ulf Silvering, a layman from Stockholm, said the canonisation of Hesselblad "means a lot to the local Catholic community in Sweden since normally the Catholic Church is described as some exotic experience from immigrants.''

However, he said "this is a Swedish saint, and it's the second Swedish saint officially in history. She's a follower of St. Bridgette, who was also Swedish, so it's a restoration of the Catholic history in Sweden, actually."

Silvering said Hesselblad's canonisation also "serves to strengthen the faith of immigrants, who live in one of the most secularised countries in the world."

St. Peter's Square was packed with thousands of people on Sunday, reports say.

The canonisation was announced last March 15 alongside that of Bl. Mother Teresa of Calcutta, who will be canonised on Sept. 4, and Bl. Jose Sanchez del Rio, who will be canonised on Oct. 16 alongside Argentine Bl. Jose Gabriel del Rosario Brochero.