Hebrews 1:6-8
“And again when He brings in the First-Begotten into the world, He says, And let all the angels of God worship Him. And of the Angels He says, Who makes His angels spirits, and His ministers a flame of fire. But unto the Son He says, Your throne, O God, is for ever and ever.”
1. Our Lord Jesus Christ calls His coming in the flesh an exodus [or going out]: as when He says, “The sower went out to sow.” And again, “I went out from the Father, and have come.” And in many places one may see this. But Paul calls it an [eisodus or] coming in, saying, “And when again He brings in the First-Begotten into the world,” meaning by this Bringing in, His taking on Him flesh.
Now why has he so used the expression? The things signified [thereby] are manifest, and in what respect it is [thus] said. For Christ indeed calls it a Going out, justly; for we were out from God. For as in royal palaces, prisoners and those who have offended the king, stand without, and he who desires to reconcile them, does not bring them in, but himself going out discourses with them, until having made them meet for the king's presence, he may bring them in, so also Christ has done. Having gone out to us, that is, having taken flesh, and having discoursed to us of the King's matters, so He brought us in, having purged the sins, and made reconciliation. Therefore he calls it a Going out.
But Paul names it a Coming in, from the metaphor of those who come to an inheritance and receive any portion or possession. For the saying, “and when again He brings in the First-Begotten into the world,” means this, “when he puts the world into His hand.” For when He was made known, then also He obtained possession of the whole thereof, He says not these things concerning God The Word, but concerning that which is according to the flesh. For if according to John, “He was in the world, and the world was made by Him”: how is He “brought in,” otherwise than in the flesh?
“And,” says he, “Let all the angels of God worship Him.” Whereas he is about to say something great and lofty, he prepares it beforehand, and makes it acceptable, in that he represents the Father as “bringing in” the Son. He had said above, that “He spoke to us not by prophets but by His Son”; that the Son is superior to angels; yea and he establishes this from the name [Son]. And here, in what follows, from another fact also. What then may this be? From worship. And he shows how much greater He is, as much as a Master is than a slave; just as any one introducing another into a house straightway commands those having the care thereof to do him reverence; [so] saying in regard to the Flesh, “And let all the Angels of God worship Him.”
Is it then Angels only? No; for hear what follows: “And of His Angels He says, Which makes His Angels spirits, and His ministers a flame of fire: but unto the Son, Your Throne, O God, is for ever and ever.” Behold, the greatest difference! That they are created, but He uncreated. While of His angels He says, who “makes”; wherefore of the Son did He not say “Who makes”? Although he might have expressed the difference as follows: “Of His Angels He says, Who makes His Angels spirits, but of the Son, 'The Lord created Me': 'God has made Him Lord and Christ.'” But neither was the one spoken concerning the Son, nor the other concerning God The Word, but concerning the flesh. For when he desired to express the true difference, he no longer included angels only, but the whole ministering power above. Do you see how he distinguishes, and with how great clearness, between creatures and Creator, ministers and Lord, the Heir and true Son, and slaves?
2. “But unto the Son he says, Your throne, O God, is for ever and ever.” Behold a symbol of Kingly Office. “A scepter of righteousness is the scepter of Your kingdom.” Behold again another symbol of Royalty.
Source: Homilies on the Epistle to the Hebrews (New Advent)