Aquinas preached two sermons on the Epistle on this particular Sunday; the first (the sermo) being preached in the morning, the second (the collatio) being preached at Vespers. The first part is presented below.
THE TEACHING OF HOLY SCRIPTURE. PART. I.
SECOND SUNDAY IN ADVENT. (FROM THE EPISTLE.)
“For whatsoever things were written aforetime were written for our
learning.” Rom 15:4.
THE Apostle has taught us on the preceding Sunday to arise from the dead; on this day he teaches us towards what we ought to arise, for the Scripture, which our heavenly Master has given for us, is to be studied and read. And the Lord as a good Master was the more solicitous to provide us with the best writings, that He might make us perfectly instructed. “Whatever things,” He said, “were written, were written for our learning.” But these writings are comprised in two books, that is to say, in the Book of Creation, and in the Book of Scripture.Note: The Homily on “The Book of Scripture” can be found here. The present homily deals with “The Book of Creation.”
The first book has so many creations: it has just so many most perfect writings, which teach the truth without a lie; hence, when Aristotle was asked whence he had learnt so many and so great things, answered, “From the things themselves, which know not how to deceive.” But they teach two things to be learned; and of the things which may be known four things are to be taught. First, that there is a God; secondly, that this God is one; thirdly, that this God is triune; and, fourthly, that He is the highest good. For the world teaches by itself that it is His work. “For by the greatness of the beauty, and of the creature, the Creator of them may be seen, to be known thereby” (Wis 13:5). Because they are one, and are preserved, in the same manner, they teach the unity of God; for, if there were many Gods, the world would have already been destroyed, since division is the cause of destruction. “Every kingdom divided against itself is brought to desolation; and every city or house divided against itself shall not stand” (Matt 12:25). For all things exist by number, weight, and measure; or, according to S. Augustine, “On the Trinity by mode, by species, and by order; so that they teach a three-fold Godhead.” “Thou hast ordered all things in measure, number, and weight” (Wis 11:21). Because all things are good, they teach that He is the highest goodness through Whom so many good things proceed. According to S. Augustine it is a great token of goodness that every creature
conceives itself to be good; therefore, because God is good, so are we.
About the actions to be done, in like manner, we are taught a four-fold lesson. God is to be obeyed, loved, feared, and praised.
Of the first, we ought to obey God, for all things serve Him. “He hath made a decree which shall not pass” (Ps 148:6). Nothing among God’s creatures does the Creator find to be disobedient, save the sinner and the devil.
God teaches us to love Him by His benefits and gifts, which He shows to us daily. Saint Augustine says that heaven and earth, and all things which are in them, on every side, say to me that I should love Thee; neither do they cease to say this by all things, that I may be inexcusable if I love Thee not.
By pains and punishments they teach us to fear God. We see that all things are prepared to punish those that rebel against their Creator. “For the creature serving Thee, the Creator, is made fierce against the unjust for their punishment: and abateth its strength for the benefit of them that trust in Thee” (Wis 16:24).
They teach us to praise God; for all things praise Him and invite us to His praising. S. Augustine says that it is wonderful that man does not always praise God, since every creature invites to the praising of Him; and this so plainly that all His creatures become as so many Scriptures of God, teaching us that there are four things to be known, as well as four commands to be performed.