Pope Francis leaves after a wedding ceremony in St. Peter's Basilica at the Vatican.  Pope Francis married 20 couples, including some who already live together and those with children, technically a sin in the eyes of the church. (AP Photo/Alessandra Tarantino)
Pope Francis leaves after a wedding ceremony in St. Peter's Basilica at the Vatican. Pope Francis married 20 couples, including some who already live together and those with children, technically a sin in the eyes of the church. (AP Photo/Alessandra Tarantino)
A section of the brides and their grooms, and their witnesses, (standing behind) pray before Pope Francis (not seen)  as he conducts a mass wedding ceremony inside St. Peter's Basilica, Vatican City. Twenty couples from the Diocese of Rome were married by the Pope. The last Pope to marry commoners was Pope John Paul II in 1979.  EPA/ANGELO CARCONI
A section of the brides and their grooms, and their witnesses, (standing behind) pray before Pope Francis (not seen) as he conducts a mass wedding ceremony inside St. Peter's Basilica, Vatican City. Twenty couples from the Diocese of Rome were married by the Pope. The last Pope to marry commoners was Pope John Paul II in 1979. EPA/ANGELO CARCONI

Vatican City - Pope Francis on Sunday was celebrating marriage for 20 couples, including some who already have kids - a sin under Catholic Church teaching.

The gesture, coming three weeks before a global meeting of bishops due to discuss family matters like premarital sex, was seen as a testimony of the pontiff's belief in a “merciful” church.

“Those who will get married Sunday are couples like many others,” the diocese of Rome, who selected the couples to be married in the Basilica of St Peter, said in a statement earlier in the week.

The ages of the newlyweds range from 25 to 56, and among them there are “those who are already living together, those who already have children, those who met in church,” the diocese said.

Gabriella, whose daughter was due to attend the wedding ceremony, told Vatican Radio she was grateful that her union with Guido, who has a previous marriage that has been annulled, was being celebrated in church.

“Because it would be a really painful sacrifice to be denied the Sacraments, the Communion and to be deprived of a live blessed by God, of a love that is blessed and experienced as it should be,” she said.

It is quite rare for a pope to celebrate public weddings. Saint John Paul II did it twice, in 1994 and 2000, while Pope Emeritus Benedict XVI never officiated the sacrament during his papacy.

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