CCC 2035 The supreme degree of participation in the authority of Christ is ensured by the charism of infallibility. This infallibility extends as far as does the deposit of divine Revelation; it also extends to all those elements of doctrine, including morals, without which the saving truths of the faith cannot be preserved, explained, or observed.1
1 Cf. LG 25; CDF, declaration, Mysterium Ecclesiae 3.