The Second Vatican Council’s Constitution Sacrosanctum Concilium proclaimed a “great principle” in article 36, recognizing the right of each liturgical assembly to pray to God in its own language. Historians remind us that the problem of liturgical language had already been faced and successfully resolved in the middle of the ninth century thanks to Saints Cyril and Methodius.
Responding to those who limited to only three the languages “in which it is licit to praise God, specifically Hebrew, Greek and Latin” – those used for the inscription on the cross – the two brother saints listed liturgical language among the goods that belong to all, like the rain “that God lets fall on all humans,” the sun “that shines on all in the same way” (cf. Mt 5:45) and the air “that everyone breathes.”
The apostolic mission of Cyril and Methodius was to the Slavic peoples. Only several centuries later did the problem arise for the Latin peoples, but this time without a successful outcome. It was the 16th century, a time full of promise but rocked by doctrinal turbulence. The Council of Trent took place in that aggravated atmosphere and was committed to containing the divisions that had afflicted parts of Christianity, and so was unable to welcome the appeals of those reformers in favor of the vernacular in the liturgy.