Catechism of the Catholic Church §2108 — excerpt
, immunity, within just limits, from external constraint in religious matters by political authorities. This natural right ought to be acknowledged in the juridical order of society in such a way that it constitutes a civil right.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: Leo XIII, Libertas praestantissimum 18 · Pius XII AAS 1953, 799 · DH 2