Chapter 1 — Preface to the Roman Catechism
Section 26. Thus, if the Gospel of the first Sunday of Advent is to be explained, There shall be signs in the sun, and in the moon, etc., whatever regards its explanation is contained under the Article of the Creed, He shall come to judge the living and the dead; and by embodying the substance of that Article in his exposition, the pastor will at once instruct his people in the Creed and in the Gospel. Whenever, therefore, he has to communicate instruction and expound the Scriptures, he will observe the same rule of referring all to these four principal heads under which, as we observed, the whole teaching and doctrine of Holy Scripture is contained. As for order, however, he is free to follow that which he deems best suited to the circumstances of persons and time.