VATICAN CITY – Pope Francis made a widespread change Saturday to the ways, and words, in which Roman Catholics worship by amending Vatican law to give national bishop conferences greater authority in translating liturgical language.

"It's hugely important," said Rita Ferrone, a specialist in Catholic liturgy who writes for Commonweal, a liberal Catholic magazine. She said that by loosening Rome's grip on the language of prayers, Francis had restored the intention of the reforms of the Second Vatican Council and erased some of Pope Benedict's rollbacks.

Francis, who celebrated mass in Colombia on Saturday as part of his visit there, has not been shy in efforts to reform the church and has tread on some of its most delicate subjects.

On Saturday, he also stepped squarely onto the Liturgy Wars, which, especially in the English-speaking church, have divided liberals and conservatives for decades.

With "Magnum Principium," a papal Motu Proprio — or a document issued under the pope's own legal authority — Francis altered a key 2001 instruction by Pope John Paul that empowered Vatican officials in Rome to ensure local translations adhered to the standard Latin.

Catholic progressives have advocated a greater use of contemporary idioms consistent with the Second Vatican Council reforms of the 1960s and many bristled under what they considered a heavy and out-of-touch hand from Rome.

Conservative opponents favor the Latin mass, or at least more faithful translations to it in the local ­language.