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.
All Commentaries on Exodus 3:2 Go To Exodus 3
Pacian of Barcelona
AD 391
What does this mean? The vision that is said to have appeared to Moses in the desert is sometimes called an angel, sometimes the Lord. It means this: he is called angel when he served by speaking externally, and Lord, because he ruled within and produced the conditions needed for speaking. For when the speaker is ruled from within, he is called both angel because of his service and Lord because of his inspiration. Exposition of the Old and New Testament, Exodus