Women are still prohibited from most jobs in the Catholic church but Pope Francis has said that the wage gap between men and women was a “pure scandal” that Christians ought to reject.

“Why is it taken for granted that women must earn less than men? No! They have the same rights,” he told tens of thousands of people at his general audience in St Peter’s Square on Wednesday.

Pope Francis was hitting on an issue that affects women across the globe. In the EU, women were paid 16.4% less than men on average in 2013, according to statistics agency Eurostat, and US Census Bureau data indicate women earn 77 cents for every dollar a man earns, based on annual median salaries.

His remarks during a general audience in St Peter’s Square were part of a broader address on the role of marriage in which the pontiff denied that women’s emancipation was responsible for the decline in the institution. Instead, he pointed a finger of blame at the “culture of the provisional”, where nothing is “definitive”.

The proclamation about women’s rights came days after the Argentinian pontiff declared another feminist truism: namely, that men and women are equal.

Recalling the story of Genesis, when God first created Adam and then created woman out of his rib to be a “helper suited to him”, Pope Francis said: “The image of the ‘rib’ does not in any way express inferiority or subordination, but on the contrary, that man and woman are of the same substance and are complementary.”

The comments this week were some of Pope Francis’s most forceful to date on the issue of gender equality. Although he has said that the “door is closed” to the possibility of women becoming priests – the Catholic church teaches that women cannot become priests because Jesus willingly chose only men as his apostles – he has said he wants women to have a bigger role within the church.

Advocates of a female priesthood reject the church’s view, saying that Jesus was acting according to the norms of his times.

Earlier this month, the Vatican brought to an abrupt conclusion a crackdown on an influential group of liberal nuns in the US who had been chastised by the church for straying too far from church teachings with “radical feminist” ideas.