Not to any men now living, but to the prophets of the Old Law, with the apostles, and some few other saints of the New. The great revelation was that made in Christ (Heb. i, 1), of which the Church is the guardian and exponent. The Church gets no new revelations. The Pope has no revelations as Pope: he takes counsel of theologians: only a special providence, such as might preserve him, e.g., from drowning, prevents his authoritatively teaching the Church any point of faith or morals that is not a legitimate unfolding of the revelation of Christ.
Of God and His Creatures: 3.155