The pastor of a Catholic parish in the Washington suburbs has publicly slammed the decision this month by Georgetown Visitation Preparatory School to allow announcements of same-sex unions in its magazine for graduates, calling it a scandal that was a “dagger to the heart” and accusing the nun who made the decision of betraying her faith.

Monsignor Edward J. Filardi, pastor of Our Lady of Lourdes Catholic Church in Bethesda, Md., wrote an open letter in Sunday’s parish bulletin in which he stated that Sister Mary Berchmans, 89, Visitation’s president emerita, wrongly interpreted church teaching on same-sex marriage and that she succumbed to lobbying from graduates who wanted the policy changed.

“Sister, I am sure this decision takes a lot of pressure off of you, secures the financial fortune of your 220 year-old academy and will make you the toast of the town,” wrote Filardi, 53. “But is it worth becoming toast? And worse leading others to the same?”

Filardi continued, “Sister, you have beautifully given yourself to God and our Church in consecrated life for 70 years and have done so much good. For this I offer my highest admiration. Why betray it now?”

Berchmans sent a letter in early May to the Visitation community in which she said the Catholic girls academy would publish same-sex union announcements in the class notes section of its magazine for graduates. The decision, she said, followed a period of “much prayerful consideration and thoughtful dialogue.”

Berchmans wrote that while the church’s teaching against same-sex marriage is clear, “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.”

In his letter Sunday, Filardi described the policy set forth by Berchmans as a “capitulation,” and quoted the Bible to emphasize that marriage can be between only a man and a woman.

“To treat any other arrangement as ‘marriage’ belittles what God has created, and mocks God, and causes great confusion,” he wrote.

Berchmans and Georgetown Visitation declined a request to comment on Filardi’s letter. The school said last week that the response to its decision had been overwhelmingly positive.

The Archdiocese of Washington also declined to comment on Filardi’s letter and pointed to its previous statement on Visitation’s decision. That statement read in part: “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. . . . Catholic Church teaching on marriage is clear, and it also does not conflict with the Gospel message of love.”

Filardi’s letter was shared online among Visitation graduates who supported Berchmans, many of whom reacted angrily to the priest’s comments.

J. Caitlin Finley, a 2000 graduate of the school, wrote in an email that she was “disturbed and deeply troubled by his response to Mother Mary Berchmans’ decision. . . . ”

She added, “I was raised by a Church that calls us to ‘love thy neighbor’ and admonishes us ‘not to judge lest ye be judged.’ Sr. Berchmans is living her faith, reminding us that we are all children of God, with inherent dignity and deserving of respect and love. Fr. Filardi, regrettably, is encouraging judgment and exclusion.”

Christina Peters, a 1980 Visitation graduate who is gay and married her partner nine years ago, was also unhappy with Filardi’s letter.

“The priest’s suggestion that Sr. Berchmans made this decision in order to secure the financial future of the school and to be the ‘toast of the town’ is offensive, and anyone who knows her at all would never believe either of those things,” Peters wrote in an email.

In an interview Wednesday, Filardi said he wrote his letter “because I feel I had a duty really to protect my parishioners from kind of a loose logic that was used to come to that decision. I think it’s dangerous moral decision-making.”

Filardi said response to his missive from parishioners has been mixed. In the interview, Filardi said that by acknowledging same-sex unions, Visitation is approving them. When asked whether announcements of marriages outside the faith or marriages by divorced Catholics or announcements of births to unmarried mothers were also a concern to him, Filardi declined to comment.

“I am happy to talk about what I wrote,” he said. “I’m just not looking to expand on that.”

While Catholic teaching forbids same-sex marriage, recent studies show support for same-sex marriage in the United States has grown among most religious denominations, including Catholics. Two-thirds of Catholics said they were in favor of same-sex marriage, according to a survey conducted in 2017 by the Public Religion Research Institute, a nonpartisan, nonprofit policy research organization. The survey was based on more than 40,000 interviews.

Filardi has used his parish newsletter to criticize same-sex marriage before. When same-sex marriage became legal in Maryland in 2013, Filardi’s letter in the church bulletin began, “Welcome to Sodom. Yes, that is what Maryland has now become.” He went on to describe Catholics who pushed for the bill’s passage, including the state’s governor at the time, Martin O’Malley, as “Satan’s helpers.”

“In promoting this desecration they have not only brought dishonor to our holy faith and shame to all Catholics, but invite the real possibility of damnation on themselves.”

Filardi became a monsignor in 2005 and has been pastor at Our Lady of Lourdes since 2009. Earlier in his career, he served as a priest secretary for then-Cardinal Theodore McCarrick and as an assistant vocations director for the diocese.

McCarrick resigned from the College of Cardinals last year following allegations that he had sexually abused minors and adult seminarians for decades. He was defrocked by the Vatican earlier this year. Filardi has said in previous interviews that when he worked for McCarrick in the early 2000s, he was not aware of the allegations against the cardinal.