In Epiphania Domini: "the Gentiles without, being as brutes, are roused not by a voice, but by a sign, that is, a star."

Homily by Pope St. Gregory the Great.
10th on the Gospels.
Dearly beloved brethren, hear ye from the Gospel lesson how, when the King of heaven was born, the king of earth was troubled? The heights of heaven are opened and the depths of earth are stirred. Let us now consider the question, why, when the Redeemer was born, an angel brought the news to the shepherds of Judea, but a star led the wise men of the East to worship Him. It seemeth as if the Jews as reasonable creatures received a revelation from a reasonable being, that is, an angel, but the Gentiles without, being as brutes, are roused not by a voice, but by a sign, that is, a star. Hence Paul hath it: a sign, not to them that believe, but to them that believe not but prophesying serveth not for them that believe not, but for them which believe. 1 Cor. xiv. 22. So the prophesying, that is, of the angel was given to them that believed, and the sign to them that believed not.

Thus also we remark that afterwards the Redeemer was preached among the Gentiles not by Himself, but by His Apostles, even as, when a little Child, He is shown to them, not by the voice of angels, but merely by the vision of a star. When He Himself had begun to speak He was made known to us by speakers, but when He lay silent in the manger, by that silent testimony in heaven. But whether we consider the signs which accompanied His birth or His death, this thing is wonderful, namely, the hardness of heart of the Jews, who would not believe in Him either for prophesying or for miracles.

All things which He had made, bore witness that their Maker was come. Let me reckon them after the manner of men. The heavens knew that He was God, and sent a star to shine over where He lay. The sea knew it, and bore Him up when He walked upon it. The earth knew it, and quaked when He died. The sun knew it, and was darkened. The rocks and walls knew it, and rent at the hour of His death. Hell knew it, and gave up the dead that were in it. And yet up to this very hour the hearts of the unbelieving Jews will not acknowledge that He to Whom all nature testified is their God, and, being more hardened than the rocks, refuse to be rent by repentance.