For some reason, the understanding of Christ pre-incarnate is very controversial, as people get confused with the "Title" which refer to Jesus. Now, Jesus is NOT a created Angel. He is fully Man, fully God, the Messiah, the Christ, and Lord and Saviour. Jesus is Eternal. Jesus was never created. Jesus is Eternal as the Father and Holy Spirit are Eternal. Jesus has always been and always will be.
Jesus is the angel of the LORD, the angel of God, the Archangel Michael, who appeared time and again in the Old Testament to speak directly to His people, prior to the incarnation.
Michael is just another "Title" to refer to Jesus just as Lamb and Lion is. Michael is not a created Angel. Michael the Archangel is only a name or title.
First let's look at the phrase 'angel of the LORD' in the story of Moses and the burning bush
And the angel of the LORD appeared unto him in a flame of fire out of the midst of a bush: and he looked, and, behold, the bush burned with fire, and the bush was not consumed.
Now look at the following verses and who is identified as being in the bush?
Exo 3:4 And when the LORD saw that he turned aside to see, God called unto him out of the midst of the bush, and said, Moses, Moses. And he said, Here am I.
Exo 3:6 Moreover he said,*I am* the God of thy father, the God of Abraham, the God of Isaac, and the God of Jacob. And Moses hid his face; for he was afraid to look upon God.
Notice that the 'angel of the LORD' is really none other than God Himself and we have more...
King James Version (KJV)
29Then fled Moses at this saying, and was a stranger in the land of Madian, where he begat two sons.
30And when forty years were expired, there appeared to him in the wilderness of mount Sina an angel of the Lord in a flame of fire in a bush.
31When Moses saw it, he wondered at the sight: and as he drew near to behold it, the voice of the LORD came unto him,
Then we have the following exchange...
And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you.
and who but Christ says this...
Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I AM.
Jesus Christ had just identified Himself as the One who is the God of the Old Testament patriarchs, who was present in the burning bush speaking to Moses and the Jews knew exactly what Jesus meant as seen in what happens.
King James Version (KJV)
57Then said the Jews unto him, Thou art not yet fifty years old, and hast thou seen Abraham?
58Jesus said unto them, Verily, verily, I say unto you, Before Abraham was, I am.
59Then took they up stones to cast at him: but Jesus hid himself, and went out of the temple, going through the midst of them, and so passed by.