Although there are both Old and New Testament references to “the angel of the Lord” and the “angel of God,” whenever the definite article “the” is used, particularly in the Old Testament, a specific and unique being is in view. While this unique entity is easily distinguishable from other angels, He often appears indistinguishable from the Lord Himself. For instance, He often speaks as God, promises to perform the works of God, and identifies Himself with God (Genesis 16:7-14; 21:17-18; 22:11-18; 31:11-13; Exodus  3:2-10; Judges 2:1-5; 6:11-24; 13:3-22). Thus, many have concluded that the angel of the Lord is actually a theophany—a physical manifestation of God.  

To further support the proposition of the angel of the Lord being a theophany, permit me to share a few additional pieces of evidence. 

1. The angel of the Lord is identified as God by some to whom He appeared (Genesis 16:7-13).

2. After encountering the angel of the Lord, an experience that they deemed equivalent to seeing God, some feared for their lives, since God had warned that no man could see His face and live (Exodus 33:20; Genesis 16:13; 32:30; Judges 13:21-23).

3. Jacob not only credits the angel of the Lord with redeeming him from all evil, but also calls upon Him to bless his grandsons Ephraim and Manasseh (Genesis 48:16).

4. God’s promised presence among the Israelites appears to have been fulfilled by the accompanying angel of the Lord (Exodus 23:20-23). 

In view of the fact that Christ is the visible and physical manifestation of God (John 1:1, 14, 18), as well as the one whose name is far more “excellent” than that of any angel (Hebrews 1:1-14), the early Church Fathers concluded that the angel of the Lord was actually a Christophany—a pre-incarnate appearance of Christ in Scripture. The fact that the frequent appearances and special role of the angel of the Lord in the Old Testament is all but absent in the New Testament certainly lends credence to this credible supposition. 

Although some object to the angel of the Lord being understood as the pre-incarnate Christ and pre-existent “Word of God” due to His seemingly subordinate role to God the Father in the Old Testament, it is neither inconsistent with the rest of Scripture nor difficult to believe that the second person of the Trinity began His mediatorial ministry between God and man before His incarnation (1 Timothy 2:5). When you consider the additional fact that the only figures in Scripture associated with the name “Wonderful” are the promised Son of God (Isaiah 9:6) and the angel of the Lord (Judges 13:18)❊, then it becomes not only plausible, but most probable, that the angel of the Lord is indeed a pre-incarnate appearance of Christ in the Scripture.

❊ The Hebrew word for “secret” in Judges 13:18 means wonderful and is the same Hebrew word that is translated “wonderful” in Isaiah 9:6.