Doctrine. The word doctrine comes, by way of the Latin doctrina, from the Greek word doxa, meaning belief. The doctrine(s) of the Church, therefore, are those teachings which must be believed by the faithful. These include 1) dogmas, teachings which the Church has solemnly defined as formally revealed by God, and, 2) other teachings definitively proposed by the Church because they are connected to solemnly defined teachings. The first (dogmas) can be called doctrines of divine faith, the second doctrines of catholic faith. Together they are said to be “of divine and catholic faith.” Both kinds of doctrine require the assent of faith. Both are infallibly taught by the Church. Dogmas require it because they are formally revealed by God. Doctrines definitively proposed by the Church require it, because the infallibility of the Church in matters of faith and morals is itself divinely revealed. A side note, doctrine shares the same root as orthodox, meaning correct belief. Those who hold the Church’s doctrines faithfully are thus orthodox.
