Pope Francis declared Mother Teresa of Calcutta a Saint on Sunday morning, stressing her commitment to the poorest of the poor, especially unborn children threatened by abortion.

“Mother Teresa, in all aspects of her life, was a generous dispenser of divine mercy,” the Pope said in his homily before the more than 100,000 people overflowing Saint Peter’s Square, “making herself available for everyone through her welcome and defense of human life, those unborn and those abandoned and discarded.”

“She was committed to defending life, ceaselessly proclaiming that ‘the unborn are the weakest, the smallest, the most vulnerable,’” Francis added.

Calling Mother Teresa an “emblematic figure of womanhood and of consecrated life,” the Pope held her up as a “model of holiness” for today’s generation.

In the canonization ceremony, the Pope pronounced the official liturgical formula of sainthood.

“We declare and define Blessed Teresa of Calcutta to be a saint and we enroll her among the saints, decreeing that she is to be venerated as such by the whole church,” the Pope said at the beginning of Mass, prompting thunderous applause from the large congregation.

On the facade of Saint Peter’s Basilica hung a huge tapestry with a portrait of Mother Teresa, one of the modern world’s most recognizable faces.

The Albanian nun founded the order of the Missionaries of Charity in 1950 with 12 followers in Calcutta, India. Once the fastest growing order in the Catholic Church, the Missionaries now run hospices, homeless shelters, institutes for the care of AIDS victims and other services for the poorest of the poor in 139 countries.

In stressing Mother Teresa’s concern for the unborn, Pope Francis highlighted an aspect of Mother Teresa’s work that she considered central.

Teresa believed abortion to be the greatest social injustice in the world. The three most public speeches of her career—her acceptance of the Nobel Peace Prize, her Harvard Commencement address, and her words at the National Prayer Breakfast in Washington DC—all focused on abortion as the world’s number one social evil, earning her the undying opprobrium of the Left.

“I am not sure exactly what heaven will be like,” Teresa once said, “but I don’t know that when we die and it comes time for God to judge us, he will not ask, How many good things have you done in your life?, rather he will ask, How much love did you put into what you did?”

Considered by many a saint already in her lifetime, Mother Teresa was beatified by Pope John Paul II on October 19, 2003, just five years after her death.

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