The church must go out and encounter young people “in detention centers, at the borders” and “in all places where their safety and family unity are threatened,” Yadira Vieyra said to the Synod of Bishops on Oct. 11. Speaking as a young immigrant living in the United States, Ms. Vieyra was sharply critical of the “hateful rhetoric and policies” she has witnessed, and she described the “sustained distress” experienced by migrants, which affects the way “they pray and remain hopeful.”

To show that the church values the lives of young people, she said the church needs to develop “innovative ways to minister to this vulnerable community” while helping people to know that Jesus Christ “stands with the oppressed and challenges the oppressor.”

Pope Francis appointed Ms. Vieyra, 29, as an auditor to the synod that is meeting from Oct. 3 to 28 in Rome to discuss “young people, faith and vocational discernment.” The synod includes 267 voting members who are mostly cardinals and bishops, 50 auditors (half men, half women) and other delegates and collaborators.

The church must go out and encounter young people “in detention centers, at the borders.”

For Ms. Vieyra, the commitment to justice for migrants is personal. Ms. Vieyra was born in Mexico and raised in the Pilsen neighborhood in Chicago. In an interview with America shortly before delivering her address to the synod, Ms. Vieyra described how immigration policies have directly affected her family and her community.

A few years ago during dinner on Christmas Eve, her family learned that her aunt had been detained. The news was so shocking for her mom that she needed her daughter to confirm what the text message actually said and to say “this is real,” Ms. Vieyra explained.

“My aunt is an example of someone who is willing to risk everything to be with family. Right now, we are experiencing a very unwelcoming environment.”

Her mother and grandfather have not seen each other since her family moved to the United States 25 years ago, but they will reunite later this month. Ms. Vieyra will be in Rome when it happens, but she said she will share in their joy.

For Ms. Vieyra, the commitment to justice for migrants is personal.

“God works in mysterious ways,” she said, expressing gratitude that she can represent the immigrant community at the Synod of Bishops. “I have to speak” on this reality.

Ms. Vieyra is a graduate of Cristo Rey Jesuit High School in Chicago, Georgetown University and the Erikson Institute in Chicago. She currently works as a research specialist in the field of child development at the University of Chicago, and she collaborates with Immaculate Conception Parish in Brighton Park through Fortaleciendo mi familia, which helps bring low-intensity cognitive behavioral therapy and psychosocial support to Mexican immigrant families experiencing distress, anxiety and depression due to community violence, financial challenges and migration-related worries.

“In my community the youth are active, they are marching,” Ms. Vieyra said. “It is important for the church to communicate that their lives matter, that every life is precious,” and that these young people can do this work as Catholics rather than being “political activists” outside the church. The church needs to communicate “we are with you” in relation to gun violence, police brutality and immigration.

The church needs to communicate “we are with you” in relation to gun violence, police brutality and immigration.

In the interview, Ms. Vieyra described several moving encounters with Pope Francis during her time in Rome.

On the second day of the synod, she said, Pope Francis told a group of auditors: “If there is something you agree with, feel free to make noise. It is O.K. to get loud. It is O.K. to clap. It is within protocol. But also remember that if someone says something that you don’t necessarily agree with, just listen respectfully.”

In the synod aula, Pope Francis listens intently to each speaker, she said. He has also “made interventions of his own about things that touch him, about things that have him thinking. That is a sign that he is very much present. He is listening. He is taking this in a very, very serious way.”

She explained that the young people have broken into applause on several occasions “when one of the cardinals or bishops says something that is true to our reality, to what we are really experiencing.”

Pope Francis “is listening. He is taking this in a very, very serious way.”

One powerful example, she said, was when Archbishop Anthony Fisher, O.P., of Sydney, Australia, used his four-minute speech on Oct. 4 to formally apologize to young people for “the failure of too many bishops” and the various ways that the church has let down young people.

For the archbishop to use his only formal address to apologize to young people on behalf of the entire church, “it moved me to tears,” she explained. “The youth erupted into applause because it takes a lot of humility to recognize that one has failed.”

But Ms. Vieyra said she has not agreed with everything the bishops have shared.

“The role of women in the church can be overlooked,” she said. “When a church leader tries to undermine the spiritual power that sisters in the church bring, it is discouraging.”

She described a sister in Chicago who is the epitome of what a sister should be: “She exudes so much peace and so much joy for the community and for God. I tell my husband: I want to be more like her. I really do. So to hear that some members of the synod feel that only priests can bring spiritual guidance to our youth robs our sisters” of what they can do.

“The role of women in the church can be overlooked.”

Ms. Vieyra, who studied theology and psychology at Georgetown University, said that issues of gender and sexuality are being “discussed extensively” within her small group. “It was controversial, it was heated.”

“A lot of people in the room agree that we need to minister to our youth today,” she said, whether they identify with the L.G.B.T. community or they are being raised in a household where it is two fathers or two mothers. I feel very passionate about that because if Jesus were here right now, he would walk away in shame knowing that we are pushing away our brothers and sisters.”

Asked about how God is at work in the synod, she spoke about the change she has seen among the bishops. Early on, she said, many of the bishops were “more guarded” around the young people. More recently, however, the interactions are “more relaxed” and the bishops are showing more interest in the views of young people and their experience of the synod.

“I think God is doing a lot of work in their hearts,” she said. “They are human, and they were once young, so they should be able to connect with us without having that fear that we might not take them as seriously anymore.”

“I envision a church that is joyful, alive, on fire and just thrilled to communicate the Gospel and who Jesus was.”

On Wednesday, Ms. Vieyra personally delivered a letter to Pope Francis on behalf of a 10-year-old girl in Chicago. She babysat the girl and her little brother for six years and is very close to the family. The girl asked Pope Francis how to better understand the mysteries of the Rosary, and the family included a photo of the girl so the pope could connect the letter to a face.

“Pope Francis was so happy when he received the letter,” she said. “Seeing this joy in something so small is exactly what our youth need. The interaction will stay with her. His genuine and joyful response will be a reminder that God loves her so much.”

“I envision a church that is joyful, alive, on fire and just thrilled to communicate the Gospel and who Jesus was,” she said. “He loved people deeply.”

“The nun at my parish is always so happy, smiling. People love working with her because as a leader she is kind, directive and so loving. We need a church like that, with priests who are so happy to share the Gospel, they just can’t wait to do it, to rush to the pulpit and share the good news.”

In her speech to the synod, Ms. Vieyra invoked the legacy of Óscar Romero, who will be canonized on Oct. 14, and called upon the church to emulate his courage. Romero reminds us that “the true home of the church is not where she is comfortable and clean but instead with those afflicted by institutions that threaten the human life,” she said. “Our mother church desires to be where she is uncomfortable, dirty and sweaty, relentlessly washing the feet of her most vulnerable children.”

We need a church that “concretely and innovatively” models the truth that “each of us has been called by our name” and that “not one of us, including our migrant young persons, is forgotten.”

Luke Hansen, a former associate editor of America, is a Catholic writer and speaker.