2 . . . For we have seen his star in the east, and are come to adore him.
Augustine: The star which the Magi saw, at Christ’s birth according to the flesh, did not rule His fate, but ministered as a testimony to Him. Further, this was not of the number of those stars, which from the beginning of the creation observe their paths of motion according to the law of their Maker; but a star that first appeared at the birth, ministering to the Magi who sought Christ, by going before them till it brought them to the place where the infant God the Word was.
Chrysostom: This was manifestly not one of the common stars of Heaven. First, because none of the stars moves in this way, from east to south, and such is the situation of Palestine with respect to Persia. Secondly, from the time of its appearance, not in the night only, but during the day. Thirdly, from its being visible and then again invisible; when they entered Jerusalem it hid itself, and then appeared again when they left Herod. Further, it had no stated motion, but when the Magi were to go on, it went before them; when to stop, it stopped like the pillar of cloud in the desert. Fourthly, it signified the Virgin’s delivery, not by being fixed aloft, but by descending to earth, shewing herein like an invisible virtue formed into the visible appearance of a star.
Remigius: Some affirm this star to have been the Holy Spirit; He who descended on the baptized Lord as a dove, appearing to the Magi as a star. Others say it was an Angel, the same who appeared to the shepherds.
Augustine: Will you ask, from whom had they learned that such an appearance as a star was to signify the birth of Christ? I answer from Angels, by the warning of some revelation. Do you ask, was it from good or ill Angels? Truly even wicked spirits, namely the daemons, confessed Christ to be the Son of God. But why should they not have heard it from good Angels, since in this their adoration of Christ their salvation was sought, not their wickedness condemned?
Leo: Besides that star thus seen with the bodily eye, a yet brighter ray of truth pierced their hearts; they were enlightened by the illumination of the true faith.
What they knew and believed might have been sufficient for themselves, that they needed not to seek to see with the bodily eye, what they saw so clearly with the spiritual. But their earnestness and perseverance to see the Babe was for our profit. It profited us that Thomas, after the Lord’s resurrection, touched and felt the marks of his wounds, and so for our profit the Magians’ eyes looked on the Lord in His cradle.
Scripture from the Douay-Rheims Bible. Commentary from St. Thomas Aquinas, Catena Aurea, Vol. I (London: Rivington, 1842).