Person
The Angel of the LORD
A pre-incarnate appearance of Christ in the Old Testament
The shadow (Old Testament)
Throughout the Old Testament, a mysterious figure called "the Angel of the LORD" keeps appearing — speaking as God, receiving worship, forgiving sins, and bearing the divine Name Himself. He meets Hagar in the wilderness (Genesis 16), stays Abraham's hand at the binding of Isaac (Genesis 22), wrestles with Jacob (Genesis 32), speaks from the burning bush (Exodus 3), and leads Israel as the Captain of the LORD's host (Joshua 5). Somehow He is distinct from the Father, and yet He is identified as the LORD Himself.
The substance (Christ)
John identifies this same eternal Word — who was with God and was God — as the One who became flesh in Jesus Christ (John 1:1, 14). The figure who appeared in shadow throughout the Old Testament steps fully into view in the Son. Every theophany of the Angel of the LORD turns out to be a glimpse of the Christ who was always there, sent from the Father, bearing His Name and His authority.
Apostolic commentary
Hebrews 1:1-3 — God, who spoke in many ways through the prophets, has in these last days spoken to us by His Son, the radiance of His glory and the exact representation of His being.
Take it in
When you read the Old Testament, keep an eye out for the Angel of the LORD — He is Christ before Bethlehem. The God who walked with Abraham, met Moses in the bush, and stood beside Joshua is the same God who walked the roads of Galilee. He has been pursuing His people from the beginning.