Thousands of people have signed a petition condemning an anti-marriage equality booklet being distributed in Australian Catholic schools.
Titled Don't Mess With Marriage and distributed by the Australian Catholic Bishops Conference (ACBA), the 17-page booklet warns against extending marriage rights to same-sex couples.
In a media release, ACBA said marriage equality would make marriage about "intensity of emotion" rather than "a union founded on sexual complementarity and potential fertility".
"Their physical, spiritual, psychological and sexual differences show [men and women] are meant for each other, their union makes them whole, and through their union 'in one flesh' they together beget children who are 'flesh of their flesh'," the booklet reads.
"They share the sameness of humanity but enjoy the difference of their masculinity and femininity, being husband and wife, paternity and maternity."
While it is unknown how many schools across Australia have distributed the booklet, at least 56 schools in the Canberra-Goulburn area, along with others in Melbourne and the Northern Territory, have given it out.
"The pastoral letter on same-sex marriage was distributed to each Catholic bishop across Australia," an ACBA spokeswoman told BuzzFeed News.
"It is at the discretion of each bishop as to what extent the pastoral letter is distributed within their local diocese."
The petition, created by 16-year-old student Georgia Simpson, describes Don't Mess With Marriage as "anti-LGBT propaganda" and urges its removal from schools.
"Please remove the ignorant and anti-gay propaganda from circulation in Australian schools regarding same-sex marriage," Simpson wrote.
"The messages contained in the Don't Mess With Marriage booklet are humiliating and degrading."
Simpson also wrote that the booklet "enforces damaging traditional gender roles through the concepts of masculinity and femininity".
On Monday, Simpson's petition had over 8,000 signatures.
ACBA denied the contents of the booklet are degrading to LGBTI people, saying they believe "every human being has great dignity".
"People with same-sex attraction must be treated with respect, sensitivity and love in the same way as every human being," the spokeswoman said.
However, ACBA don't believe marriage equality is necessary for LGBTI people and their relationships to be treated with respect.
"Surely there are other ways of honouring the friendships of same-sex attracted and other people without further deconstructing marriage and the family," said ACBA Chair Archbishop Anthony Fisher.
Tim Christodoulou, partnerships manager at LGBT youth charity Minus18, said the booklet could ultimately prove harmful to LGBTI students.
"LGBTI young people in Australia do experience disproportionately high amounts of bullying and abuse, both at home and at school," he told BuzzFeed News.
"And this pamphlet and letters like this send the message that homophobia is OK, and that's something that's really dangerous."
Christodoulou also hit out at ACBA's assurance that same-sex attracted people must be treated with "respect, sensitivity and love".
"This letter from the Bishops' Conference says people who experience same sex attraction should be treated with respect, sensitivity and love, but on the page immediately following it says they don't think same sex relationships can ever amount to marriage."
"That sends a very, very clear message that same sex couples and gay and lesbian people across Australia aren't the same as everyone else."
Don't Mess With Marriage also focuses on procreation, mothers, and fathers, arguing that introducing marriage equality would be "gravely unjust" for children.
However, Christodoulou said this focus is harmful to the 30,000 families in Australia with same-sex parents.
"There aren't words in the English language to describe how hurtful and how delegitimising to same-sex families stuff like this can be," he said.
"It's flying in the face of all the research that says children of same-sex families are as happy and healthy, if not happier and healthier, than those with straight parents."
Although same-sex couples raising kids is a reality regardless of marriage in Australia, ACBA don't think the point is moot.
"The Church attests to the importance for children to have, as far as possible, both a mother and a father," the spokeswoman said.
"The Catholic Church believes that respecting a child's dignity means affirming his or her need and natural right to a mother and a father. Additionally, the Church makes every effort to support single parents and families."