I was reading Exodus 3 where Moses was confronted with the burning bush. It says that an angel of the Lord appeared to him. My question is about the angel of the Lord that has appeared multiple times in the Bible. Do you know if this angel of the Lord is a separate being from God himself? Or is this just a means of physically appearing to man?
The correct phrase in Exodus 3:2 is “the angel of the Lord.” The definite article distinguishes this incident from those where “an angel of the Lord” appears. “An” angel can be any of the countless angels in heaven, but many theologians believe “the” angel often refers to the pre-incarnate Jesus. As you say, there are numerous such visits in the Old Testament.
In John 10:30 Jesus said, “I and the father are one” and in John 14:9 He said, “Anyone who has seen me has seen the Father” meaning that when God wants to be visible to man He appears as His Son. Colossians 1:15 and Hebrews 1:3 confirm this.