The letter landed in email inboxes early in May, and since then, students, parents and graduates of Washington’s prestigious Georgetown Visitation Preparatory School have talked of little else. It has been the subject of spirited discussions, emotional exchanges, fervent Facebook posts.

Sister Mary Berchmans, the school’s president emerita, wrote the letter that has provoked so many reactions. In her carefully worded missive that emphasized following “the Gospel commandment of love,” Berchmans said the 220-year-old Catholic girls academy will publish announcements of same-sex unions in its alumnae magazine.

The decision, which stands in contrast to official church teaching on same-sex marriage, was greeted with a mixture of responses by the school community. Some called it “beautiful” and “overdue.” Others labeled it a “great disappointment.” In some quarters, there was unhappiness it took so long for the school to reach this point, while a smaller number expressed anger that the school was veering from Catholic doctrine.

The school’s decision followed a push last month by several ­hundred graduates who learned of an alumna who was told a few years ago that she could not have her marriage announced in the publication because it was a same-sex union. The graduates formed a chat group on Facebook to discuss the issue and urge the school to change its policy.

In her letter, Berchmans, who graduated from Visitation in 1948 and was its headmistress for many years, wrote, “Recently, a Visitation friend invited me to reflect upon what it means to Live Jesus in relationship with our ­LGBTQ alumnae.”

That conversation — as well as “much prayerful consideration and thoughtful dialogue” — led the school to its new policy, she wrote.

In previous years, Visitation’s practice was to deny requests by graduates to have their same-sex unions announced in the magazine. Occasionally, those announcements made it into the “Class Notes” section of the magazine without drawing attention, but officially they were not allowed. Now, that has changed.

Berchmans alluded to that change with a quote from St. Francis de Sales, which she chose to begin her letter: “The Church is a garden patterned with unlimited flowers; it is necessary that they should be of various sizes, various colors, various odors, and, to sum it up, different perfections . . . all of them provide a beauty most pleasing and perfect.”

Her letter went on to address the Catholic Church’s teaching on same-sex marriage and its emphasis on the Gospel’s command to love one another.

“As a professed Sister of the Visitation for 67 years, I have devoted my life in service to the Catholic Church,” she wrote. “The Church is clear in its teaching on same-sex marriages. But, it is equally clear in its teaching that we are all children of God, that we each have dignity and are worthy of respect and love.

“As I have prayed over this contradiction, I keep returning to this choice: we can focus on Church teaching on gay marriage or we can focus on Church teaching on the Gospel commandment of love. We know from history — including very recent history — that the Church, in its humanity, makes mistakes. Yet, through the grace of God and the power of the Holy Spirit, it learns and grows. And so, we choose the Gospel commandment of love.”

Christina Peters, a 1980 Visitation graduate who is gay and married her partner nine years ago when same-sex marriages became legal, said she was profoundly moved by Visitation’s decision.

“To see the school stand with gay and lesbian students and parents and families, I just felt really emotional and grateful,” Peters said. “I do suspect there will be people who will be upset and outraged about it, but Visitation has kind of made its point, and I don’t think they’re going to back off of it now.”

Peters said she had a rich and positive experience at Visitation and is close to many of her former classmates. But she also said the church’s teaching on same-sex marriage was one of the reasons she did not send her daughters to Catholic school.

Berchmans declined an interview request. So far, there have been few complaints about the policy shift from students, parents and the school’s alumnae, according to school officials.

“The response to Sister’s letter has been huge. It has been overwhelmingly and heartwarmingly positive,” said Caroline Coleman Handorf, the school’s director of communications.

The Archdiocese of Washington said in a statement it was not made aware of the school’s decision before the letter from Berchmans was sent. Although Visitation is independent, the archdiocese said in its statement: “The archdiocese has a clear responsibility to ensure independent Catholic schools maintain their authentic Catholic identity and provide advice and guidance on such matters as they arise. In the past, Georgetown Visitation has consulted the archdiocese on matters related to upholding Catholic identity, and therefore, it is especially disappointing that this consultation and collaboration was not followed.”

It continued, “Catholic Church teaching on marriage is clear, and it also does not conflict with the Gospel message of love.”

A parent of a current student, who spoke on the condition of anonymity because she worried she would be targeted for her comments, said she was disappointed with the school’s decision and that she and other parents are concerned about their children’s Catholic formation at the school. She said that opposition to the new policy is “widespread” and that many parents are still deciding how they will react.

“We chose to send our children to a Catholic school, through great sacrifice, as the tuition is pretty high, because we want Catholic doctrine and Catholic values instilled in our children before they head out into the world,” she said. “The Church’s teachings on matters of sexuality are healthy and give our girls great grounding. We feel the Catholic faith is really crucial to these girls’ successes, and . . . a lot of us are feeling very cheated right now.”

Founded in 1799, Visitation is one of the oldest Catholic girls schools in the United States. Annual tuition for the 500 students at the 23-acre campus in Georgetown is $30,100. A monastery on the grounds is home to 14 Visitation sisters, although none of them is a faculty member.

Francis DeBernardo, executive director of New Ways Ministry, an advocacy group for LGBTQ Catholics, said he was not aware of any other Catholic high school alumni magazines that include announcements of same-sex unions. He described the letter from Berch­mans as “beautiful and very powerful.”

“This is a really big step forward,” DeBernardo said. “This is something that all Catholic schools are eventually going to have to deal with, sooner rather than later. Marriage equality is a reality. Too often, Catholic leaders try to bury their heads and pretend this is not a reality, but it is.”

Jenny Baker Moore, a 1990 Visitation graduate who lives in McLean, Va., and whose family has deep ties to the school, said the change was overdue.

“Things happen at a snail’s pace in the Catholic Church, so this is a big deal,” she said. “I love the school, and I’m glad they’ve finally done this.”

Although there has been widespread support for the school’s position, some Visitation graduates in the Facebook discussion said the letter from Berchmans should be used as a springboard for the school to address additional issues of diversity, inclusion and equity.

“This stirred up a lot of pain for some people,” said Elizabeth Early, a 1992 graduate who lives in Washington and participated in the Facebook chat group. “It kind of created a big storm beyond just the awareness and acknowledgment of gay marriage. We need to look at what more the school can do.”