God continued to set forth the fact that Jesus Christ is better than the angels. The angels were created by God/Jesus Christ. They are sometimes referred to as “sons of God”, but they are not the Son of God.
The writer here was directed to quote from Psalm 2:7:

7 I will declare the decree: the LORD hath said unto me, Thou art my Son; this day have I begotten thee.

The apostle Paul referenced this passage in Acts 13:33:

33 God hath fulfilled the same unto us their children, in that he hath raised up Jesus again; as it is also written in the second psalm, Thou art my Son, this day have I begotten thee.

The writer also referenced another Old Testament passage:

II Samuel 7:14 I will be his father, and he shall be my son. If he commit iniquity, I will chasten him with the rod of men, and with the stripes of the children of men:

In that passage God was speaking to king David regarding the building of the temple. David’s son, Solomon, would build the temple and God spoke of how he would deal with him. This passage has a prophetic application to the Lord Jesus Christ being the Son of God. Of course the chastening would not apply to Jesus Christ. It is well accepted that this passage finds its fulfilment in the Lord Jesus Christ.
The best commentary on the Scriptures is always the Scriptures. God gave His Word in an orderly manner. He laid it out as needed for man to understand more fully.
In verse 6 the writer continued to refer to Old Testament passages to further shed light on Who Jesus Christ is. He is the “firstbegotten” of the Father. In Psalm 89:27 we read of Him:

Psalms 89:27 Also I will make him my firstborn, higher than the kings of the earth.

Then in Colossians the apostle Paul stated the following:

Colossians 1:15 Who is the image of the invisible God, the firstborn of every creature:

In Psalm 97 we read:

Psalms 97:7 Confounded be all they that serve graven images, that boast themselves of idols: worship him, all ye gods.

The “gods” in that passage is a reference to the angels. They bow before Jesus Christ. We know even from the birth of Jesus Christ that the angels sang praises at His birth. As we see further in our text, they are ministering spirits and they ministered to Jesus on several occasions.
In verse 7 we see further reference to Old Testament writings. This entire passage is rich in references to the Old Testament. God gave teaching in the Old Testament that helped saints like Simeon and Anna anticipate the coming of the Messiah and in knowing Who He was when He came.

Psalms 104:4 Who maketh his angels spirits; his ministers a flaming fire:

The Pharisees and others like them rejected the Scriptures except to use them as a tool to suppress the truth and to keep the people in bondage. However, the Scriptures are greater than the false teachers who twist them. Those who will listen to the Word of God and to the Holy Spirit as He seeks to open people’s eyes, will be blessed by the truth. The rest will stumble their way through life and find out too late that they rejected the most precious and important truth given to man.
In verse 8 we have more yet to add to this treasure of Jesus Christ. In Psalm 45:6 we read:

Psalms 45:6 Thy throne, O God, is for ever and ever: the sceptre of thy kingdom is a right sceptre.

There we see that the Old Testament saints were told that Jesus Christ, the king that would reign from the throne of David, is God. That is not a surprise to those who are saved. It is a truth that was rejected by the Pharisees and their crowd. It is a truth still rejected today by the Catholics and other cults.
The Catholics like to boast that their popes come from the lineage of Peter. They have nothing to boast of there. Peter was a married man and he certainly was not infallible as the Popes like to claim they are. The wise person accepts God’s Word as truth and rejects the lies of the false teachers.
Jesus Christ is also declared to have a royal throne and He and His throne are also declared to be for ever and ever.

Verse 9 of our text is a reference to Psalm 45:7:

Psalm 45:7 Thou lovest righteousness, and hatest wickedness: therefore God, thy God, hath anointed thee with the oil of gladness above thy fellows.

In Psalm 45:7 we are reminded that Jesus Christ’s throne would be one of righteousness. Jesus Christ loves righteousness and thus He hates iniquity. Further we see that God has anointed Him with the oil of gladness above His fellows. Jesus Christ is greater than all of His creation and in our text He is greater than the angels.
In Acts 10:38 Peter declared:

Acts 10:38 How God anointed Jesus of Nazareth with the Holy Ghost and with power: who went about doing good, and healing all that were oppressed of the devil; for God was with him.