QUOTATION: The True Catholic

He is the true and genuine Catholic who loves the truth of God, who loves the Church, who loves the Body of Christ, who esteems divine religion and the Catholic Faith, above every thing, above the authority, above the regard, above the genius, above the eloquence, above the philosophy, of every man whatsoever; who sets light by all of these, and continuing steadfast and established in the faith, resolves that he will believe that, and that only, which he is sure the Catholic Church has held universally and from ancient time.

--St. Vincent of Lérins, Commonitory.

QUOTATION: The Rule of Faith

It always was, and is today, the usual practice of Catholics to test the true faith by two methods; first, by the authority of the divine Canon, and then, by the tradition of the Catholic Church. Not that the Canon is insufficient in itself in each case. But, because more interpreters of the Divine Word make use of their own arbitrary judgment and thus fall into various opinions and errors, the understanding of Holy Scripture must conform to the single rule of Catholic teaching—and this especially in regard to those questions upon which the foundations of all Catholic dogma are laid.

--St. Vincent of Lérins, Commonitory for the Antiquity and Universality of the Catholic Faith

QUOTATION: Doctrine

If one yields ground on any single point of Catholic doctrine, one will later have to yield later in another, and again in another, and so on until such surrenders come to be something normal and acceptable. And when one gets used to rejecting dogma bit by bit, the final result will be the repudiation of it altogether.

-- St. Vincent of Lerins