ts 7:53: "You [Vulg.: 'who'] . . .
have received the Law by the disposition of angels." And the
Gentiles, especially astrologers, were wont to observe the course of
the stars. And therefore Christ's birth was made known to the
righteous, viz. Simeon and Anna, by the interior instinct of the Holy
Ghost, according to Luke 2:26: "He had received an answer from the
Holy Ghost that he should not see death before he had seen the Christ
of the Lord." But to the shepherds and Magi, as being occupied with
material things, Christ's birth was made known by means of visible
apparitions. And since this birth was not only earthly, but also, in
a way, heavenly, to both (shepherds and Magi) it is revealed through
heavenly signs: for, as Augustine says in a sermon on the Epiphany
(cciv): "The angels inhabit, and the stars adorn, the heavens: by
both, therefore, do the 'heavens show forth the glory of God.'"
Moreover, it was not without reason that Christ's birth was made
known, by means of angels, to the shepherds, who, being Jews, were
accustomed to frequent apparitions of the angels: whereas it was
revealed by means of a star to the Magi, who were wont to consider
the heavenly bodies. Because, as Chrysostom says (Hom. vi in Matth.):
"Our Lord deigned to call them through things to which they were
accustomed." There is also another reason. For, as Gregory says (Hom.
x in Evang.): "To the Jews, as rational beings, it was fitting that a
rational animal [*Cf. I, Q. 51, A. 1, ad 2]," viz. an angel, "should
preach. Whereas the Gentiles, who were unable to come to the
knowledge of God through the reason, were led to God, not by words,
but by signs. And as our Lord, when He was able to speak, was
announced by heralds who spoke, so before He could speak He was
manifested by speechless elements." Again, there is yet another
reason. For, as Augustine [*Pope Leo] says in a sermon on the
Epiphany: "To Abraham was promised an innumerable progeny, begotten,
not of carnal propagation, but of the fruitfulness of faith. For this
reason it is compared to the multitude of stars; that a heavenly
progeny might be hoped for." Wherefore the Gentiles, "who are thus
designated by the stars, are by the rising of a new star stimulated"
to seek Christ, through whom they are made the seed of Abraham.

Reply Obj. 1: That which of itself is hidden needs to be manifested,
but not that which in itself is manifest. Now, the flesh of Him who
was born was manifest, wher