Andrew Medichini, Associated Press
In this Sept. 10, 2014 file photo, Pope Francis walks at St. Peter's Basilica during his weekly general audience in St. Peter's Square, at the Vatican.

VATICAN CITY — Pope Francis is making good on his insistence that the Catholic Church welcome all faithful — not just those who obey church teaching perfectly. He'll marry 20 couples this weekend, including some who already live together and those with children, technically a sin in the eyes of the church.

Sunday's mass wedding in St. Peter's Basilica was timed to coincide with the start of a major two-year study by the Vatican of a host of issues affecting family life, including premarital sex, contraception and divorce. No major changes in church teaching are foreseen, but Francis has made clear that he wants people in "irregular" partnerships to feel fully a part of the church.

The diocese of Rome, which is organizing the ceremony, said the 20 couples being married range in age from those in their mid-20s to those in their 50s and include "those who are already living together, those who already have children, those who met in church."

Francis already set a precedent of sorts back in January when he baptized the child of a couple who hadn't married in the church, but only in a civil ceremony.

His decision to marry couples who are technically living in sin is another sign of his desire for a more merciful and forgiving church that cares less about morals and rules than it does about the conversion of souls.

Francis has frequently lamented that many people today think marriage is just a temporary arrangement and not a lifelong commitment.

"You're the courageous ones, because you have to have courage to get married today," he told newlyweds who attended his Wednesday general audience last week, dressed in their bridal whites and tuxedos.

St. John Paul II presided over public weddings twice during his pontificate — in 1994 and in 2000. Emeritus Pope Benedict XVI didn't celebrate the sacrament during his pontificate.

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