Angel of the Lord
The Angel of the Lord (Hebrew mal'ak YHWH) appears in numerous Old Testament theophanies as a divine messenger who speaks and acts as God himself, receiving worship appropriate to God alone (Gen. 16:7-13; Ex. 3:2-6; Judg. 6:11-24). The figure is simultaneously identified with and distinguished from God: the Angel says 'I am the God of Bethel' (Gen. 31:13) and those who encounter him fear they have seen God face to face (Judg. 13:22). Many theologians identify the Angel of the Lord as a pre-incarnate Christophany — a visible appearance of the Son of God before the incarnation.
Smith's Dictionary notes that the formula 'the Angel of God' appears interchangeably with 'the Angel of the Lord' and that both designations apply to a being who is manifestly divine yet distinguishable from the Father. After the incarnation, 'angel of the Lord' in the NT refers to a created angelic being rather than this distinctive OT figure. The Angel of the Lord comforts Hagar (Gen. 16), calls to Abraham on Moriah (Gen. 22:11), guards Israel in the wilderness (Ex. 14:19), and commissions Gideon (Judg. 6:12) — making him the primary visible vehicle of God's direct presence with his people throughout the OT narrative.