He was the Messenger of the LORD who was sent by the LORD and is the LORD?
Yes. There is a threefold fullness being described here in the verses about this encounter between Moses and the Angel of the LORD.
The Holy Spirit is wanting us to understand Who the Angel of the LORD is.
And the Angel of the LORD appeared to him in a flame of fire from the midst of a bush. So he looked, and behold, the bush was burning with fire, but the bush was not consumed. Then Moses said, “I will now turn aside and see this great sight, why the bush does not burn.”
So when the LORD saw that he turned aside to look, God called to him from the midst of the bush and said, “Moses, Moses!”
And he said, “Here I am.”
Then He said, “Do not draw near this place. Take your sandals off your feet, for the place where you stand is holy ground.” Moreover He said, “I am the God of your 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. Exodus 3:2-6
The Angel of the LORD is the LORD, and is God.
God the Son, not God the Father.
God the Father is God.
God the Son is God.
And Moses hid his face, for he was afraid to look upon God.
JLB