MINNEAPOLIS, Minn. — As the battle heats up in Minnesota over a proposed state constitutional ban on same-sex marriage, there has been renewed outrage by statements expressed by Twin Cities Catholic Archbishop John Nienstedt in a 2010 letter to one of his parishioners.

The Minneapolis Star Tribune, which published Nienstedt’s letter last weekend as part of an article about the prelate’s aggressive efforts in support of the constitutional amendment, reported that the May 2010 letter was in response to a note from “a mother who pleaded for acceptance for her gay child.”

In the letter, Nienstedt wrote that Catholics are obligated to believe the Church’s official teachings on homosexuality, and that “those who do not… ought not to participate in the sacramental life of the Church,” and advised the mother that her “eternal salvation” could be in jeopardy:

I write to inform you that the teaching of the Catholic Church on homosexuality, as described in paragraphs 2357 and 2358 and 2359 of the Catechism of the Catholic Church is rooted in Scripture and based on the Natural Moral Law. It, therefore, shares in God’s revelation to us. Catholics are bound in conscience to believe this teaching. Those who do not cannot consider themselves to be Catholic and ought not to participate in the sacramental life of the Church. Indeed, some might find this is a hard saying by many of Jesus’ teachings were likewise received as such. I urge you to reconsider the position that you expressed in your letter. Your eternal salvation may well depend upon a conversation of heart on this topic.

In a statement Tuesday, Truth Wins Out Executive Director Wayne Besen called it “appalling that Archbishop Nienstedt chose to issue such an un-Christian response to a vulnerable member of his flock who came to him seeking help. The archbishop’s letter shows just how deeply held his anti-gay views are.”

“Telling the parent of an LGBT child that she ‘ought not to participate in the sacramental life of the Church’ unless she renounces her pro-equality views – and that her ‘eternal salvation may well depend upon’ her willingness to accept the Catholic Church’s anti-gay teachings – is spiritual bullying of the highest order and utterly reprehensible,” added John Becker, Director of Communications & Development for Truth Wins Out.

“What kind of spiritual leader demands that a mother reject her child in order to save her soul?” said Becker.

Nienstedt’s letter also brought a swift reaction from LGBT ally, Minnesota Vikings player Chris Kluwe, a vocal supporter of marriage equality who has recently taken anti-gay legislators to task.

Kluwe wrote:

“Tell me, Archbishop, Pope, what purpose does the Church serve attempting to influence the affairs of a secular state? The federal benefits under law currently denied gay couples certainly fall under the realm of Caesar, don’t they? No one is forcing the Catholic Church to marry gay couples if that is not the Church’s wish. You can keep the sanctity of Catholic marriage solely between heterosexual couples if you feel that is what’s required (again though, I caution you on the dangers of presumed infallibility). All we are asking is for you to extend the open hand of tolerance instead of the closed fist of fear and hate. As American citizens, we respect the right for everyone to practice whichever religion they so choose, including the right to not practice one at all. Haven’t we learned enough from the Crusades, the Inquisitions, the Talibans of the world? What does it benefit the Church to attempt to influence secular policy in this country, especially when that influence is to deny basic human rights to others? Will you now assume Caesar’s throne, grasping the transitory ephemera of worldly power and control, while forsaking the eternal kingdom of Heaven?”

According to a 2009 study conducted by San Francisco State University researcher Caitlin Ryan and published in the Journal of the American Academy of Pediatrics, such rejection can have devastating consequences for LGBT youth.

LGBT teens who experienced negative feedback from their families were 8 times more likely to have attempted suicide, 6 times more vulnerable to severe depression, and 3 times more likely to use drugs than teens who did not experience negative feedback.

Polling results released Tuesday by Public Policy Polling finds support for the marriage ban running slightly behind its opposition.

According to the poll, 46 percent of voters planning to support the ban, while 49 percent oppose it, a a 4 point shift compared to a month ago when it led for passage 48-47.