ROME — A group of men and women religious from the southern Italian regions of Sicily and Calabria have condemned measures adopted by interior minister Matteo Salvini to curb illegal immigration into the country.

In a letter dated March 6 — which marked the beginning of the Christian season of Lent — but released by national media on Wednesday, the Catholic sisters and brothers denounced Mr. Salvini’s Security Decree, as well as the minister’s remarkable popularity, even among Catholics.

The Decree, which exemplifies the “banality of evil,” attempts “to regulate the presence of migrants in the national territory, denying them every possible humanitarian protection,” the letter reads.

“We wish to express our total disagreement with this muscular and simplistic way of dealing with the issue of migrants,” the religious declare.

Otherwise, our silence would mean becoming “accomplices of a style of thinking, governing, and acting, which in fact obscures the humanity of the other, reducing him to an annoying bother, to a dangerous illegal immigrant, to an enemy to fight and eliminate,” the letter states.

“The favorable reception that such a style has had and has with so many people living in the North and in the South, and, what is very worrying for us, among many people who frequent the various churches,” it says, “all this strengthens us in the conviction that we cannot remain silent, because the path taken does not lead us to grow, but to diminish in humanity.”

A survey conducted last summer found Mr. Salvini to be the most trusted politician in all of Italy, earning him the ranking of a “superstar” with the Italians.

By October, Salvini’s party La Lega (League) had become the most popular political party in the nation, with a voter affiliation of 33.8 percent, a striking rise from its status as an outlying regional party just five years ago.

In their searing letter, the southern Italian religious said that Salvini’s Decree denies immigrants “the status of humanity.”

The letter lamented that many of today’s Christians have rejected the hospitality practiced by the early Church, trading it for xenophobia.

“Choosing one or the other word is not indifferent to our human, cultural and religious journey both on a personal level and on a level of civil coexistence,” they said.

Closing borders to migrants is “inhuman,” the letter states, and reflects an overemphasis on the complex problems of immigration without weighing “the positive experiences made in this regard.”

“The demonization of the migrant” has become “the scapegoat for all of Italy’s ills,” the letter says, drawing attention away from “our real problems,” such as the existence of the mafias, the problem of corruption, land management, tax evasion, and a lack of respect for the dignity of human life.

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