Vatican: Pope Francis urged Christians to recognize the suffering of others because it would be a grave sin to ignore it.

The pope added that the plight of those who suffer today should motivate Christians to offer new signs of mercy. He made the comments on Sunday, Sept. 3, to the pilgrims in Rome for Mother Teresa’s canonization.

“I will never tire of saying that the mercy of God is not some beautiful idea but rather a concrete action,” the pope said. “There is no mercy without concreteness. Mercy is not doing something good while passing by; it means involving yourself there where there is evil, where there is sickness, where there is hunger, where there is human exploitation,” he added.

The pope and the pilgrims listened to testimonies of people who devoted their lives to serve others. Sister Mary Sally shared how she was filled with love and enthusiasm despite the violence in Yemen. She belongs to the Missionaries of Charity founded by Mother Teresa, and the sole survivor of an attack at a nursing home that killed 16 people.

“We beg God to continue using our nothingness to make the church present in the world today through the mission entrusted to us by our Mother Teresa, even amid dangerous surroundings,” she said.

Pope Francis told the audience that the Church cannot turn its back on those who are crying out for mercy. He thanked the volunteers for their work and acknowledged that they are “among the most precious things in the church.” He also encouraged them to follow Mother Teresa’s example before leading them in a silent prayer, reported Christian Times..

Around 120,000 gathered at St. Peter’s Square the next day to witness the canonization ceremony of Mother Teresa. The pope highlighted her dedication to defend the life of the unborn and took note of her courage to confront powerful people.