He was eternally the Son of God.
There is one God eternally in three persons. Father, Son and Holy Spirit. They are one in their divine nature. They together as one are the Most High God, above all other gods, omniscient, omnipotent, and omnipresent. My position is the historic and biblical view.
Jesus is the Creator
Acts 7:
49‘Heaven is My throne
and the earth is My footstool.
What kind of house will you build for Me, says the Lord,
or where will My place of repose be?
50Has not My hand made all these things?
John 1:
1In the beginning was the Word, and the Word was with God, and the Word was God.
2He was with God in the beginning.
3Through Him all things were made, and without Him nothing was made that has been made. 4In Him was life, and that life was the light of men.
5The Light shines in the darkness, and the darkness has not overcome it.
It is clear from Hebrews that those were the last days, and that Christ's throne was eternally existent.
Hebrews 1:
1Long ago, at many times and in many ways, God spoke to our fathers by the prophets,
2but in these last days he has spoken to us by his Son, whom he appointed the heir of all things, through whom also he created the world.........
8But of the Son he says, (Quoting Psalms 45:6)
“Your throne, O God, is forever and ever,
the scepter of uprightness is the scepter of your kingdom.
It was the Israelites who became the enemies of Christ when they rejected Him and wanted a king like the other nations, and rejected Him again Luke 19:27 where He calls them His enemies and would have them slain. So when Christ used the Roman armies in 70 ad, that's when His enemies were put under His feet. He is our king and we are the true Israel of God.
The Son does the will of the Father, not the other way around, which establishes that Christ is subordinate to the Father, and is the significance of being seated at the right hand of his Father’s throne in Psalm 110.
John 5:30 I can of mine own self do nothing: as I hear, I judge: and my judgment is just; because I seek not mine own will, but the will of the Father which hath sent me.
Only the Father knows that Day that Christ returns; again, this relates Christ is subordinate to the Father.
Matthew 24:
36 But of that day and hour knoweth no man, no, not the angels of heaven, but my Father only.
Hebrews 1 does not support your unorthodox views. Verse 2 relates the Father has “appointed” Christ “heir of all things,” and “by whom also” God “made the worlds” (the translated pronouns “he” pertain to the Father). The Old Testament also supports verse 2.
Genesis 1
26 And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth. (my emphasis)
Proverbs 8:
22 The LORD possessed me in the beginning of his way, before his works of old.
23 I was set up from everlasting, from the beginning, or ever the earth was.
24 When there were no depths, I was brought forth; when there were no fountains abounding with water.
25 Before the mountains were settled, before the hills was I brought forth:
26 While as yet he had not made the earth, nor the fields, nor the highest part of the dust of the world.
27 When he prepared the heavens, I was there: when he set a compass upon the face of the depth:
28 When he established the clouds above: when he strengthened the fountains of the deep:
29 When he gave to the sea his decree, that the waters should not pass his commandment: when he appointed the foundations of the earth:
30 Then I was by him, as one brought up with him: and I was daily his delight, rejoicing always before him;
31 Rejoicing in the habitable part of his earth; and my delights were with the sons of men.
Hebrews 1:4 declares that Christ has “by inheritance obtained a more excellent name” than all the angels, which maintains that Christ is divine because he is the Son of God, even before the foundations of the world. The Son is subordinate to the Father even at the establishment of the new heavens and earth, which Paul relates in First Corinthians and the Revelation advances.
1 Corinthians 15:
24 Then cometh the end, when he shall have delivered up the kingdom to God, even the Father; when he shall have put down all rule and all authority and power.
25 For he must reign, till he hath put all enemies under his feet.
26 The last enemy that shall be destroyed is death.
27 For he hath put all things under his feet. But when he saith, all things are put under him, it is manifest that he is excepted, which did put all things under him.
28 And when all things shall be subdued unto him, then shall the Son also himself be subject unto him that put all things under him, that God may be all in all.
Revelation 21:
1 And I saw a new heaven and a new earth: for the first heaven and the first earth were passed away; and there was no more sea.
2 And I John saw the holy city, new Jerusalem, coming down from God out of heaven, prepared as a bride adorned for her husband.
3 And I heard a great voice out of heaven saying, Behold, the tabernacle of God is with men, and he will dwell with them, and they shall be his people, and God himself shall be with them, and be their God.
Paul held that the Father is the exception to Christ’s reign because the Father can never be subordinate to the Son. Is your father subordinate to you? You need to read the Fifth Commandment again. In essence, in the presence of the Father Christ submits to the Father’s rule. The Son is not a peer to the Father. Consequently, the prophecy that Christ rules David’s throne must have its dominion on earth, while his Father is still in Heaven. It is the only logical interpretation of “Christ’s reign.” So long as Christ is in the direct presence of the Father, the Father rules because the Son is always subordinate.
You conspicuously neglected to deal honestly with Hebrews 2:8, “not yet all things put under him.” Do you really want to try and defend that the ancient Romans were willing to have Christ reign over them? And if not then they were also enemies of Christ. To this day Christ has enemies that do evil and have not subjected themselves to him on earth. And that is the worst part of amillennialism when it tries to indoctrinate people into buying that Christ is reigning over this evil world since the time of the crucifixion. What I read in God’s word is that Christ’s reign gathers the descendants of Israel and Judah to their own land and establishes justice on the earth, which is certainly not the case now.
Jeremiah 23:
5 Behold, the days come, saith the LORD, that I will raise unto David a righteous Branch, and a King shall reign and prosper, and shall execute judgment and justice in the earth.
6 In his days Judah shall be saved, and Israel shall dwell safely: and this is his name whereby he shall be called, THE LORD OUR RIGHTEOUSNESS.
7 Therefore, behold, the days come, saith the LORD, that they shall no more say, The LORD liveth, which brought up the children of Israel out of the land of Egypt;
8 But, The LORD liveth, which brought up and which led the seed of the house of Israel out of the north country, and from all countries whither I had driven them; and they shall dwell in their own land.
Isaiah 2:
2 And it shall come to pass in the last days, that the mountain of the LORD'S house shall be established in the top of the mountains, and shall be exalted above the hills; and all nations shall flow unto it.
3 And many people shall go and say, Come ye, and let us go up to the mountain of the LORD, to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for out of Zion shall go forth the law, and the word of the LORD from Jerusalem.
4 And he shall judge among the nations, and shall rebuke many people: and they shall beat their swords into plowshares, and their spears into pruninghooks: nation shall not lift up sword against nation, neither shall they learn war any more.