To me it seems that in the Old Testament there are a succession of Prophets. What is to say that Christ instead of being both the son of God and God Himself was not only a Prophet? Moses could also perform miracles and was a great leader. Yet he was not considered the son of God? In this case can we say that Christ was only a Prophet of God?
Moses was son of God. King David was. In some sense, even Cyrus the Great, the pagan king of Persia, he was, too. Because there is a sonship of rulers who were anointed by God and set aside for his purposes.
Psalm 2 was read at the ordination/coronation of a Davidic king. This is what it says:
"I will surely tell of the decree of the LORD:
He said to Me, ‘You are My son,
Today I have begotten You.
'Ask of Me, and I will surely give the nations as Your inheritance,
And the very ends of the earth as Your possession.
‘You shall break them with a rod of iron,
You shall shatter them like earthenware.’
Now therefore, O kings, show discernment;
Take warning, O judges of the earth.
Worship the LORD with reverence
And rejoice with trembling.'
Do homage to the son, that He not become angry, and you perish in the way,
For His wrath may soon be kindled.
How blessed are all who take refuge in Him!"
Now, after the conquest of Israel, there were no more Davidic kings, no more sons of God, no more anointed ones. The Hebrews prophecied that one day there would finally be another anointed one, another son of God: Greater than all the others, who would save Israel from all of his iniquities and liberate the Hebrews. This one was called "Messiah". The Messiah was considered different from the other sons of God because he would bring Israel's glory to all the earth.
Jesus claimed to be that Messiah, that son of God, different from all the rest. And we believe that he saved Israel from all his iniquities, and spread the glory of Israel to all the earth. Legend has it that the dying words of the last pagan emperor of Rome were: "Thou has conquered, O Galilean!" referring to Jesus.
Now, because Jesus is the final and ultimate son of God, there is something else about him. God was his Father, we believe, from before all eternity. So he inherited the human sonship of David, but he also united that Davidic sonship with his eternal sonship when he made intercession for Israel upon the mercy seat in the heavenly temple, upon the Cross, and in the pit of Sheol. This made it so that all the Royal Priests of Israel could become eternal sons of God like him, uniting heaven and earth. This fulfills what was said by God through his prophet Hosea:
"In that day I will also make a covenant for them
With the beasts of the field,
The birds of the sky
And the creeping things of the ground.
And I will abolish the bow, the sword and war from the land,
And will make them lie down in safety.
I will betroth you to Me forever;
Yes, I will betroth you to Me in righteousness and in justice,
In lovingkindgness and mercy,
I will betroth you to Me in faithfulness.
Then you will know the LORD.
'It will come about in that day that I will respond,' declares the LORD.
“I will answer the heavens, and they shall answer the earth..."