Pope Francis canonized Mother Teresa in front of a crowd of 120,000 onlookers at the Vatican on Sunday morning. The iconic Albanian nun, now officially St. Teresa of Calcutta, has been venerated for her work caring for those who were sick and poor in India and around the world, with 517 clinics in 100 countries at the time of her death.

Hundreds of handmade signs littered St. Peter’s Square in support of the founder of the Missionaries of Charity order. Teresa won the Nobel Peace Prize in 1979 for her humanitarian work. “Always a saint in our hearts, now a saint for all the world,” read one such tribute. Monday marks the 19th anniversary of Mother Teresa’s death, making her canonization one of the fastest in the church’s history—thanks, in part, to the late Pope John II. He expedited the process and approved her first miracle after her 1997 death. (In order to be declared a saint, the Catholic Church must agree the candidate lived virtuously and performed at least two miracles through the intercession of God.)

Pope Francis secured Teresa’s legacy by approving her second miracle late last year and by canonizing her today. "She bowed down before those who were spent, left to die on the side of the road, seeing in them their God-given dignity," Pope Francis said. "She made her voice heard before the powers of this world, so that they might recognize their guilt for the crime of poverty they created."

"We may have some difficulty in calling her 'Saint' Teresa," Pope Francis added. "Her holiness is so near to us, so tender and so fruitful, that we continue to spontaneously call her Mother."

But very few legacies are without controversy, and there are other reasons some will find difficulty calling Teresa a "saint." Some have raised questions about where the money donated to her order by those "powers of the world" came from—and where it went: Several doctors' accounts reported that her clinics for the sick provided inadequate care in "unfit" conditions.

Today, nuns and priests continue her order's work around the world.
