As an outspoken critic of modern “decadence”, Cardinal Juan Luis Cipriani, the hardline archbishop of Lima, might be expected to set a spotless moral example.

He has launched excoriating attacks on everything from single mothers and gay rights to human rights activists, while even questioning a state pension of just £25 a month for some of Peru’s poorest citizens on the grounds that it discourages thrift. He has also called for mercy for paedophile priests.

So it came as a surprise this month when it was claimed that Cardinal Cipriani, one of just two Catholic cardinals in Opus Dei, the group that advocates a literalist interpretation of the bible, had been plagiarising in his columns in El Comercio, the newspaper of record for the Peruvian Establishment.

Local website spotted that the archbishop had copied and pasted entire paragraphs from the speeches and writings of two popes, Benedict XVI and Paul VI. The first signs came in an op-ed on 10 August, in which the cardinal had apparently lifted a section from Benedict’s book Communion. Aimed at justifying the role of the church in public life, the archbishop seemed to have copied almost verbatim a stretch of the book that begins: “The first service that faith offers politics is to free man from the irrationality of political myths that constitute the real threat in our time.”

The archbishop responded by playing down the scandal. In a letter to El Comercio, he claimed the arguments in his column were part of the “patrimony of the teachings of the Catholic Church”, and as such had no copyright. But he did concede: “I regret that the brevity of space led me to omit these sources and I recognise the error.”

The newspaper’s reaction was swift. It took down the offending articles from its website and put out a statement, saying: “It is clear that the daily will not publish more articles by the cardinal.”

That was a major step for an outlet that has been a mouthpiece of the Peruvian elite since 1839. The paper had recently moved so far right that the novelist Mario Vargas Llosa famously pulled his column from it in 2011, arguing that it was churning out propaganda on behalf of presidential candidate Keiko Fujimori, the unrepentant daughter of former president Alberto Fujimori. He is now serving a 25-year jail term for corruption and directing death squads.

Cardinal Cipriani’s explanation about space – his op-ed actually took up an entire page – also met with ridicule from El Comercio’s main rival, centre-left paper La República. Columnist Augusto Alvaro Rodrich wrote: “Not even the most sycophantic of his acolytes believes that.” Another writer, Raul Tola, added that even a “primary school student” would not get away with such an excuse.

The scandal is the latest blow to the archbishop, one of the church’s most senior ultra-conservative clerics, who has been gritting his teeth since Pope Francis began steering the Vatican in a more liberal direction.

During that time the archbishop has lowered his profile. But he has still come out with a string of blunt opinions, including describing the US Supreme Court’s green light to gay marriage as a “tragic decision”. He also opposed a recent attempt to allow abortion in Peru for rape victims, demanding: “Let them show that this raped woman wants to kill her child.”

And he even launched a bizarre attack on texting app WhatsApp, asking: “How many families have broken up through WhatsApp? You will say that I am exaggerating, or a retrograde, but no, someone has to say the truth.”