“Sisters for life!” Madonna tweeted in October. She wasn’t referring to Lady Gaga or Rihanna: her affection was directed at Sicilian nun Sister Cristina Scuccia, who has recorded a cover of the US pop star’s 1984 hit Like a Virgin.

The singing nun – who invited the audience to join her in reciting the Lord’s Prayer after winning The Voice of Italy talent show in June – today releases her debut album. She claims her cover of the racy classic is more of “a secular prayer than a pop song”, telling Catholic newspaper Avvenire: “If you read the lyrics without being influenced by what has gone before, you discover that it is a song about the capacity of love to make people new again, to release them from their past. And that’s how I wanted to interpret it. That’s why we’ve transformed it from the pop-dance track it was into a romantic ballad.”

The 26-year-old argues: “I chose it myself, without any desire to provoke or scandalise.” Yet Italy’s Religious Information Service news agency called it a “reckless and sly commercial operation”. Holy Sisters are not always cut from the same cloth: BBC Culture picks out some of Sister Cristina’s ground-breaking predecessors, including an erotic poet and a 1960s activist.

Sister Juana Inés de la Cruz

“I shall not play the slenderness/Of your fine, exquisite torso/For the bend of your waist is as/Troubling as a trill in the song.” These lines were not penned by a male poet, but by a Mexican nun who was born out of wedlock in the country’s central highlands. Juana entered a convent in 1667 at the age of 16, and wrote plays, essays and poetry that challenged the views of the day.

With her Response to Sister Filotea, she defended a woman’s right to education, becoming one of the first published feminists in the New World; her love poems to the wife of the viceroy stray beyond friendship to obsession. Some of her words even veer into Katy Perry territory: “Loving you is a crime/For which I shall never atone,” she wrote. “It does not matter if you elude my arms/my dear, when thought alone can imprison you.”

After a bishop anonymously circulated one of her letters – in which she criticised a priest’s sermon – she was forced to stop writing and sign a renewal of her vows, which she did in her own blood.

Hildegard von Bingen

Celebrated as a 12th-Century visionary, mystic and composer, Hildegard also stood up against prevailing views. The 10th child of a noble family, she was sent to an anchoress at the age of eight after experiencing visions, and went on to establish two convents in the Rhine valley. She wrote to the Pope urging him to work harder on reforming the Church, and provided a Christian burial for a man who had been excommunicated, arguing he had repented on his deathbed.

Among her writings on philosophy and natural history, there are several references to sexual desire, including one section that has been called the first description of the female orgasm. Referring to sensuality between men and women, the passage is seen as a progressive counterpoint to the view of sex as unclean.

Corita Kent

Born in Iowa, Sister Corita taught art in Los Angeles for 21 years and became famous for her Pop Art prints during the 1960s and ‘70s. Her messages of love and peace chimed with the counterculture of the time, and she offered a spiritual take on consumerism, elevating advertising logos and signage to the level of the divine.

Corita left the church in 1968, her artwork moving away from co-opting brand packaging and increasingly addressing issues like civil rights and the Vietnam War. When the US Postal Service launched her design for the 1985 ‘Love Stamp’ at the studio where The Love Boat had been filmed, Corita declined to attend, objecting to a link between the love she illustrated and the saccharine romance of the TV series.

By subverting consumerism and engaging with the social movements of the 1960s, Corita created a radical art that has seen her called “Warhol with a conscience”. In one work, she included the lines “I admire people who march./ I admire people who go to jail./ I don’t have the guts to do that./ so I do what I can.”

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